7 named CCSP principals, 30K+ studies, helped author the IRS Audit Techniques Guide. $1.5M+ qualifier explicitly excludes small residential.
- 7 named CCSP principals
- Co-author IRS Pub 5653
- 25+ yrs · A+ BBB · CPA-preferred
Cost Seg Smart
8.0/10$495 entry tier, same federal methodology (Rev. Proc. 87-56, IRS Pub 5653) as $5K+ providers. The 10× spread buys documentation depth, not a bigger deduction.
- Cheapest full-study pricing
- Audited against IRS Pub 5653
- 60-day money-back guarantee
Cost Segregation Authority
8.0/10Strongest audit-defense claim in the industry: zero IRS adjustments across 30K+ studies. In-house engineers + CPAs review every report.
- Zero IRS adjustments / 30K+ studies
- 20+ yrs; in-house engineering + CPA
- §179D / §45L incentives bundled
Cost Seg Smart
8.0/10Built for the segment big firms qualify out of (traditional engineering firms min: $1.5M+). $795 buys the same federal classification a $5K provider produces, minus the unrequired site visit.
- Tiers cover $200K–$2M residential
- STR FF&E calibrated to vacation rentals
- Under-1-hour turnaround
Engineered Tax Services
7.8/1025 yrs · 75K+ studies · $2B+ saved · 98% satisfaction. Named case studies with disclosed dollar amounts. AICPA member.
- 75K+ studies / $2B+ saved
- Named case studies with $ amounts
- AICPA member · CPA partnership program
Cost Seg Smart
8.0/10Under 1 hour. Only firm in the 27-provider dataset that publishes turnaround time. Industry benchmark is 4–8 weeks. Engineer signs off on each report before delivery.
- Under 1 hr vs. industry 4–8 wks
- Engineer signs every report
- No site visit (Pub 5653 doesn't require one)
Most mature CPA partnership in the category, co-branded deliverables, CCSP-signed reports, audit-defense scope CPA peer-review recognizes.
- Co-branded · CCSP-signed
- Most mature CPA partner program
- Sub-$1M lane: CSS partner program
How to read the rankings. Each card carries the category, the named provider, and the rubric score. Cost Seg Smart appears in three category cards (operator-disclosed inline); Cost Segregation Authority, Engineered Tax Services, and Capstan Tax hold the other four. Same six-criteria methodology applied to all 27 providers.
How the top 4 compare on the things that actually matter.
Eight rows of objective, verifiable facts. No spin, every value reflects what the provider publishes on their own site or has confirmed to industry reports. Where ties exist, they're listed as ties.
| Criterion | Cost Seg Smart | traditional engineering firms | Engineered Tax Services | Cost Segregation Authority |
|---|---|---|---|---|
| Residential STR study price | $495–$895 | $3,500+ (quote-only) | $3,000–$12,000 (FAQ-disclosed) | $6,000–$12,000 (industry-reported) |
| Published turnaround time | Under 1 hour | 4–6 weeks (industry benchmark) | "Schedule consultation" | "Schedule consultation" |
| Methodology basis | IRS Pub 5653 | IRS Pub 5653 | IRS Pub 5653 | IRS Pub 5653 |
| Audit defense scope | Included w/ named scope | Included | "Audit support materials in deliverables" | Zero IRS adjustments / 30K+ studies |
| Engineer sign-off | Every study | Every study (CCSP-credentialed) | Every study (licensed engineering firm) | Every study (in-house engineers + CPAs) |
| Sample report available | Public download | Request only | Request only | Request only |
| Pricing transparency | Published tiers on site | Quote-only | Quote-only (FAQ-acknowledged range) | Quote-only |
| Target property size | $200K–$3M | $1.5M+ qualifier | $1M+ commercial bias | $1M+ multifamily / commercial |
Cost Seg Smart wins 4 of 8 rows on objective facts (price, turnaround, sample report, pricing transparency). Cost Segregation Authority wins audit defense on the zero-adjustment track record. traditional engineering firms and ETS lead on credibility-by-volume rather than head-to-head facts. All four apply the same federal methodology. Values reflect public claims as of May 2026.
Every top-10 provider, in plain language.
The good, the bad, and when to skip them entirely. Click any row to expand.