We built DepreciMax, so we're biased — but we believe it's the only pre-purchase cost segregation tool that actually analyzes a specific property rather than returning regional averages from a few typed inputs. If you want a mobile-friendly cost seg tool for your Airbnb, there are no native iOS or Android apps in this category — everything runs on web. What is marketed as a "cost seg app" splits into three honest buckets: (1) pre-purchase AI (DepreciMax) — $99 per property, analyzes the actual listing photos; (2) free lead-generation calculators (Cost Seg EZ Free Estimate, Cost Segregation Guys Free Proposal, FreeCostSeg Free Calculator) that return regional averages from typed inputs to funnel you into the vendor's paid study; and (3) entry-tier paid engineer-signed studies delivered through mobile-friendly web workflows (Cost Seg EZ Engineer-Reviewed from ~$895, R.E. Cost Seg Rapid Report from $950, FreeCostSeg from $1,200). For larger properties, complex engagements, or name-brand audit defense, the traditional engineering firms covered in our cost segregation firms roundup are the actual best conversation. This article covers only the self-serve / web-first category.
TL;DR — the three honest buckets of cost seg "apps" for Airbnb hosts (2026)
• Native iOS or Android apps: none exist. Every tool below is a mobile-friendly web tool.
• Pre-purchase AI, property-specific: DepreciMax — $99 per property. AI analyzes the actual listing photos. Runs before you write the offer.
• Free pre-purchase calculators, regional-average: Cost Seg EZ Free Estimate, Cost Segregation Guys Free Proposal, FreeCostSeg Free Calculator. Return a regional average from typed inputs. Explicit lead-gen for the vendor's paid study.
• Entry-tier paid engineer-signed studies (post-close): Cost Seg EZ Engineer-Reviewed from ~$895, R.E. Cost Seg Rapid Report from $950, FreeCostSeg from $1,200. The deliverable you file with your return.
• Where to go for the actual best cost seg deliverables (larger properties, complex engagements, name-brand audit defense): the traditional engineering firms in our cost segregation firms roundup.
How we evaluated the tools
For each tool below we reviewed vendor public materials, confirmed pricing where published, and categorized by delivery (web vs. desk-review), timing (pre-purchase screening vs. post-purchase filing), and output (property-specific analysis vs. regional-average estimate). Tools are listed by bucket, not ranked within a bucket.
Bias disclosure. DepreciMax is the publisher of this article. We built it because we believe pre-purchase AI analysis of a specific property's listing photos is categorically different from a regional-average calculator — and that no other tool on the market currently does the pre-purchase job. We cover the free calculators and the entry-tier paid studies factually because they are legitimate options at a different step in the deal, not because we recommend them over DepreciMax for the pre-purchase moment. Judge for yourself after reading the comparison below.
Are there real “apps” for Airbnb cost segregation?
Short answer: no native mobile apps. If you search “cost segregation app” in the iOS App Store or Google Play as of 2026, you will not find a dedicated cost segregation tool. The category runs entirely on web. That is not a limitation — every tool below is designed to work from an iPhone or Android browser, and intake flows are built for the small screen (DepreciMax specifically supports uploading or linking listing photos from a phone browser). The practical difference between “app” and “web tool” for this use case is nothing. Pick the tool, not the delivery form.
What Airbnb hosts actually need from a cost segregation tool
Three variables determine fit for an individual Airbnb host:
1. Timing in the deal. If you have not closed yet, you need a pre-purchase screen that tells you whether the property's economics justify committing to it. If you have closed, you need an engineer-signed study you can file with your return. Different tools serve different moments. The free calculators try to serve both; they do neither as well as a dedicated tool.
2. Property specificity. A $400K Pigeon Forge cabin with a hot tub, outdoor kitchen, and finished basement will produce a very different Year-1 deduction than a $400K suburban home with no outdoor amenities — even though both might look identical to a general-stats calculator. A property-specific tool looks at the actual property; a general-stats calculator asks for typed inputs (sqft, bedrooms, zip) and returns a regional average.
3. IRS-filing posture. If you need the number for a tax return, you need an engineer-signed study, period. Pre-purchase estimates and free calculators are not IRS-filable on their own; they feed the decision of whether to commission the engineer-signed study.
The cost segregation tools compared
| Tool | Delivery | Pre- or Post-Purchase | Price | Engineer-Signed | Best For |
|---|---|---|---|---|---|
| DepreciMax | Mobile-friendly web tool; property-specific photo + assessor analysis | Pre-purchase (before offer) | $99/property or $249/mo Pro (3-month min) | No (not a filed study) | Airbnb hosts screening a specific property before writing the offer |
| FreeCostSeg (Modern CFO) | Mobile-friendly web tool; AI-assisted engineer-signed study | Post-purchase | $1,200–$5,000 flat (most residential $1,200–$1,600) | Yes (ASCSP-member sign-off) | Airbnb hosts who have closed and want the lowest-cost engineer-signed study |
| Cost Seg EZ | Mobile-friendly web tool; three-tier (DIY / Engineer-Reviewed / Fully Engineered) | Post-purchase | ~$895 Engineer-Reviewed; from ~$2,500 Fully Engineered | Yes (Engineer-Reviewed and above) | Airbnb hosts who want to pick an output tier based on expected deduction size |
| R.E. Cost Seg Rapid Report | Mobile-friendly web tool; residential-focused flat-fee study | Post-purchase | $950+ Rapid Report (sub-$1.2M residential); $2,320+ Fully Engineered | Yes | Airbnb hosts in sub-$1.2M residential who want published flat-fee pricing |
| Cost Segregation Guys | Web intake form; free rep-reviewed proposal, paid study | Post-purchase | Free proposal; paid study $2,000–$4,500 single-family | Yes (paid study) | Airbnb hosts who want a human-reviewed proposal before committing to the paid study |
| Free calculators (Cost Seg EZ, Cost Segregation Guys, FreeCostSeg) | Instant web form; typed inputs only | Pre-purchase (general stats) | Free (lead-gen for paid study) | No | Hosts who want a rough industry-average number before deciding whether to buy the paid study |
On pricing: Figures reflect vendor-published pricing current as of the publish date. Only DepreciMax, R.E. Cost Seg, FreeCostSeg, and Cost Seg EZ publish specific per-study pricing. Always get a written quote before committing.
Tool-by-tool breakdown
1. DepreciMax (deprecimax.com)
What it offers. A mobile-friendly web tool that takes a property address and returns a Year-1 bonus depreciation estimate for that specific property, using Claude Opus analysis of 7–25 listing photos combined with the county assessor land ratio. $99 per property, $249/mo Pro (unlimited reports, 3-month minimum, $99 credit toward first month when upgrading from a single report), $499–$1,299/mo Firm. Runs in under 10 minutes in any mobile or desktop browser.
Customer type. Pre-purchase buyer. Also works for (a) existing Airbnb owners who did not run cost seg at close and are deciding whether to commission a look-back study, and (b) long-term rental investors who qualify as real estate professionals under IRC §469(c)(7)(B). Not a cost segregation study, not IRS-filable on its own.
2. FreeCostSeg / Modern CFO (freecostseg.com)
What it offers. AI-assisted engineer-signed cost segregation studies, $1,200–$5,000 flat (most single-family residential $1,200–$1,600), with sign-off from an ASCSP-member engineer (Matthew Gigantelli, M009-25). Instant online benefit estimator on the home page. Lifetime IRS defense bundled into the paid product. Founded 2024.
Customer type. Post-close Airbnb host. Residential owners who want the lowest-priced engineer-signed study available. Works especially well for straightforward single-family short-term rentals.
3. Cost Seg EZ (costsegez.com)
What it offers. A three-tier product: a DIY tier, an Engineer-Reviewed tier (around $895 for residential under $1M), and a Fully Engineered tier (from around $2,500 residential). Princeton, New Jersey. Short-term rental is listed as a supported property type.
Customer type. Post-close Airbnb host. Residential owners who want to pick an output tier based on expected deduction and CPA requirements. The Engineer-Reviewed tier is often the sweet spot for sub-$500K Airbnbs.
4. R.E. Cost Seg Rapid Report (recostseg.com)
What it offers. Two engineer-signed products: a Rapid Report starting at $950 for sub-$1.2M residential (single-family through 4-unit, cap-ex under $80K), and a Fully Engineered study from $2,320 residential, $2,730+ commercial. Houston, Texas. Marketing explicitly covers Airbnb and short-term rentals.
Customer type. Post-close Airbnb host. Residential owners who want published flat-fee pricing on a straightforward property. If the property is complex (major renovations, outbuildings, mixed-use), the Fully Engineered tier scales up.
5. Cost Segregation Guys (costsegregationguys.com)
What it offers. Web intake form that delivers a free rep-reviewed proposal within about 5 hours of submission. Paid study runs $2,000–$4,500 for single-family. Flat-fee pricing (no contingency-based pricing — aligns with the IRS's preferred engagement structure). Fully virtual, no on-site visit required.
Customer type. Post-close Airbnb host. Hosts who want a human to review the property details before being quoted. The intake form requires name, email, phone, and property type — expect sales follow-up.
6. Free pre-purchase calculators
What they offer. Cost Seg EZ, Cost Segregation Guys, and FreeCostSeg each publish a free calculator that returns a Year-1 deduction estimate from typed inputs (purchase price, year built, square footage, property type, sometimes zip). Instant web output. All three are explicit lead-gen funnels for the vendor's paid study.
Customer type. Any Airbnb host who wants a free industry-average number on a specific property. Not property-specific — two different properties with identical typed inputs come back with identical numbers, even when their actual finishes, outdoor amenities, and land ratios differ meaningfully.
Screen your Airbnb before you write the offer
Where DepreciMax fits — property-specific vs. regional-average
DepreciMax isn't the only pre-purchase tool in the "cost seg app" category. Cost Seg EZ, Cost Segregation Guys, and FreeCostSeg all publish free pre-purchase calculators as well. The difference is what the tool actually looks at before producing a number:
| Pre-purchase tool | What it analyzes | Output | Price |
|---|---|---|---|
| DepreciMax | Property-specific: 7–25 of the actual listing photos (interior, exterior, outdoor amenities), the actual property address + county assessor land ratio, and the actual listing details. Claude Opus classifies the real finishes, appliances, and 15-year land improvements the buyer sees in the photos. | Year-1 bonus depreciation estimate specific to that property, with land-ratio range and tier context across 197 US STR markets. | $99 / property |
| Cost Seg EZ Free Estimate | General-stats: a handful of typed inputs (purchase price, year built, property type, square footage). No analysis of the actual property's finishes or amenities. | Regional-average deduction range for a property with those typed characteristics. Lead-gen for the firm's paid study. | Free (lead-gen) |
| Cost Segregation Guys Free Proposal | Rep-reviewed general-stats: similar typed inputs plus five-hour rep review. Still no actual-property analysis before the number is generated. | Rep-generated estimated Year-1 savings range + flat quote for the paid study. | Free (lead-gen) |
| FreeCostSeg Free Calculator | General-stats: typed inputs (purchase price, property type, zip). Returns an instant estimate without looking at the actual property. | Estimated benefit range + flat-fee quote for FreeCostSeg's paid study. | Free (lead-gen) |
The free calculators and DepreciMax both run before close, but they are solving different problems. If an Airbnb host wants a rough industry-average number on one specific property they already have under contract, the free calculators are fine — faster and no cost. If a host is comparing candidate Airbnbs and the per-property number has to be based on the actual listing (not an industry average), the general-stats calculators flatten too much of the signal: two properties with identical sqft and purchase price can produce very different Year-1 deductions depending on their actual finishes, outdoor amenities, and land ratio, and that difference is what the pre-offer decision turns on.
When a web tool is enough vs. when you need a full engineered study
For a sub-$500K Airbnb with straightforward finishes and no unusual outbuildings, a published-pricing engineer-signed study ($895–$2,500) from Cost Seg EZ, R.E. Cost Seg, or FreeCostSeg is typically sufficient. These three vendors sign their work with a licensed engineer and the deliverable meets the IRS Cost Segregation Audit Techniques Guide.
For a luxury Airbnb above $1M, multi-building compounds, mixed-use properties, or anything with major renovations after purchase, a traditional engineering firm (KBKG, Engineered Tax Services, Capstan Tax Strategies, CSSI, or Madison SPECS — covered in detail in our cost segregation firms roundup) is usually the right call despite the higher price point.
Pre-purchase screening is a separate decision. If you are evaluating multiple Airbnbs or trying to decide whether to write an offer at all, DepreciMax runs that step for $99 per property before you commit. For a deeper look at when free calculators flatten too much signal, see our free calculator vs. $99 AI vs. $5K formal study breakdown.
How to pick the right tool for your Airbnb
Four questions, in order:
- Have you closed yet? If no, start with DepreciMax ($99 pre-purchase screen). If yes, skip to question 2.
- Is the property under $1M purchase price? If yes, pick between Cost Seg EZ (~$895 Engineer-Reviewed), R.E. Cost Seg Rapid Report ($950), or FreeCostSeg ($1,200+) based on which pricing fits your CPA's requirements. If no, consider a traditional engineering firm.
- Does your CPA require a specific firm? Ask before you commit — some CPAs are comfortable with any engineer-signed deliverable; others insist on name-brand engineering firms for anything above a certain deduction threshold.
- Did you buy years ago without a study? You can still do a look-back study via Form 3115 §481(a) adjustment — all the firms above handle this. DepreciMax can screen the property first for $99 to help you decide whether the look-back is worth commissioning.
Screen your Airbnb before you write the offer — $99
Paste any Airbnb or short-term rental address. Get a Year-1 bonus depreciation estimate from listing-photo AI analysis — in under 10 minutes. Then engage one of the engineer-signed study vendors above after you close.
Run a Property Report — $99 →Frequently Asked Questions
Are there native iOS or Android cost segregation apps for Airbnb?
No. As of 2026 there are no native mobile cost segregation apps on the iOS App Store or Google Play. Every tool marketed as a "cost segregation app for Airbnb" is a mobile-friendly web tool accessed from a browser. DepreciMax, FreeCostSeg, Cost Seg EZ, Cost Segregation Guys, and R.E. Cost Seg all run in the browser.
Can I run a cost segregation estimate from my phone?
Yes. All of the major web tools render on mobile. DepreciMax runs a pre-purchase estimate from a property address and listing photos on an iPhone or Android browser in under 10 minutes for $99. FreeCostSeg and Cost Seg EZ accept intake from mobile as well. You will not get a native app experience, but you also do not need one.
What is the cheapest cost segregation tool for a $400,000 Airbnb?
For a pre-purchase screen, DepreciMax is $99 per property. For a post-purchase engineer-signed study, Cost Seg EZ Engineer-Reviewed starts around $895, R.E. Cost Seg Rapid Report at $950, and FreeCostSeg at $1,200. Free calculators from the same vendors cost $0 but return industry-average estimates, not property-specific analysis.
Do free cost segregation calculators work for IRS filing?
No. Free calculators from Cost Seg EZ, Cost Segregation Guys, and FreeCostSeg return estimates for screening and are explicit lead-gen for the vendor's paid engineer-signed study. The IRS Cost Segregation Audit Techniques Guide expects an engineering-based study with property-specific documentation for a filed deduction.
What does DepreciMax do that free calculators do not?
DepreciMax analyzes the actual listing photos of a specific property — 7 to 25 interior, exterior, and amenity shots — plus the county assessor land ratio to produce a property-specific Year-1 bonus depreciation estimate. Free calculators ask for sqft, bedrooms, and zip and return a regional-average deduction range, so two properties with identical typed inputs come back with identical numbers even when their actual finishes differ.
Can I use a web tool for pre-purchase screening and still get an engineer-signed study after close?
Yes. The two steps stack in sequence. Use DepreciMax before you write the offer to decide whether to buy, then engage FreeCostSeg, R.E. Cost Seg, Cost Seg EZ, or a traditional cost segregation firm after you close to produce the engineer-signed study you file with your return.
How fast can I get cost segregation results for an Airbnb?
A DepreciMax pre-purchase estimate returns in under 10 minutes for $99. R.E. Cost Seg's Rapid Report turns around in days for sub-$1.2M residential. FreeCostSeg's engineer-signed study typically takes a week. Cost Segregation Guys delivers a free rep-reviewed proposal within 5 hours of intake. Traditional engineer-signed studies from larger firms run 2 to 6 weeks post-close.
Does Airbnb report my depreciation deductions to the IRS?
No. Airbnb reports your rental income to the IRS on Form 1099-K when thresholds are met, but Airbnb does not calculate or report depreciation. Depreciation — including bonus depreciation under IRC §168(k) — is calculated by you (or your CPA) from a cost segregation study filed with your Schedule E, Form 4562, and in some cases Form 3115 for look-back adjustments.
Sources & further reading
Tool facts in this roundup were sourced from each vendor's public materials as of the publish date at the top of the page. Verify any pricing or feature claim before signing an engagement.
- DepreciMax: deprecimax.com
- FreeCostSeg (Modern CFO): freecostseg.com
- Cost Seg EZ: costsegez.com
- R.E. Cost Seg: recostseg.com
- Cost Segregation Guys: costsegregationguys.com
- IRS — Cost Segregation Audit Techniques Guide: irs.gov cost segregation ATG
- IRS Publication 946 — How to Depreciate Property: irs.gov/publications/p946
Vendor names, pricing, and feature descriptions were current as of the publish date and were sourced from each vendor's public website. Nothing in this article is tax, legal, or engagement advice — confirm your situation with a licensed CPA before filing.