A cost segregation study is only as good as the methodology behind it, and methodology is exactly what a marketing page will not tell you. Here is how to evaluate a provider and what separates a defensible study from an expensive spreadsheet.
My BnB Accelerator, LLC is a real estate acquisition firm, not a CPA firm, and nothing here is tax advice. Our tax partner is AE Tax Advisors, an independent firm.
The approaches are not equivalent
Providers use different methodologies, and the IRS has published guidance discussing approaches and what constitutes a quality study. In broad terms, engineering based approaches that identify and cost actual components carry more weight than approaches that apply general percentages or rules of thumb to a purchase price.
The practical translation: a study that examines the property, identifies specific assets, and documents how each was valued produces a report that can be explained under scrutiny. A study that applies a template percentage produces a number that cannot.
Seven questions to ask a provider
- What methodology do you use, and how is it documented in the report? Ask to see a sample report with the client details removed.
- Do you perform a site visit or a structured remote inspection? If remote, what specifically do you require from me and how is it verified?
- Who signs the report, and what are their qualifications? Engineering and construction cost expertise matter here.
- What happens if the study is examined? Ask specifically what support is included and whether it costs extra.
- How do you handle the land allocation? Land is not depreciable, and an aggressive land allocation is a soft spot in a weak study.
- How many studies have you performed on short-term rentals specifically? Property type matters, because the asset mix in a cabin with a hot tub differs substantially from an office building.
- What does the report cost, and what is included in that price? Compare like for like rather than headline numbers.
The classification question comes before the provider question
A study determines how large a deduction is. It does not determine whether you can use it. If the activity has long average stays or you are not materially participating, the resulting loss may suspend regardless of how good the study is. Answer that first. See the seven day rule and material participation.
We introduce clients during acquisition
Study quality, timing, and the exit conversation all belong before closing. That is why the tax introduction happens early rather than in April.
Apply NowTiming considerations
- The placed-in-service year governs the applicable bonus depreciation percentage, not the year the study is performed. Two identical properties bought in different years produce different outcomes. See bonus depreciation in 2026.
- A study can be performed on a property owned for years, with the change generally implemented through an accounting method change rather than amended returns. See look-back studies.
- Model the exit before commissioning the study, because accelerated depreciation reduces basis and increases gain on sale. See depreciation recapture explained.
Keep the report permanently
The study is not a one year document. Your CPA needs it at exit to calculate recapture, and it is the primary support for the position if the return is ever examined. Store it with your closing file rather than in an email thread. See building a documentation file that holds up.
Our tax partner publishes its own material on cost segregation studies and short-term rental tax strategy for readers who want more technical depth.
Keep reading
Frequently asked questions
What makes a good cost segregation study?
Methodology. Engineering based approaches that identify and cost actual components, document how each was valued, and address the land allocation carry substantially more weight than approaches applying general percentages to a purchase price. Ask to see a sample report with client details removed.
What should I ask a cost segregation provider?
What methodology they use and how it is documented, whether they perform a site visit or structured remote inspection, who signs the report and their qualifications, what support is included if the study is examined, how the land allocation is handled, how many short-term rental studies they have done, and exactly what the price includes.
Does it matter when the cost segregation study is performed?
The applicable bonus depreciation percentage is set by the year the property was placed in service, not the year the study runs, so two identical properties bought in different years produce different results. Studies can also be performed on properties owned for years through an accounting method change.
How long should I keep a cost segregation report?
Permanently. Your CPA needs it at exit to calculate depreciation recapture, and it is the primary support for the position if the return is examined. Store it with the closing file rather than in an email thread where it will be lost in three years.