Yes. Bonus depreciation under IRC Section 168(k) applies to property with a recovery period of 20 years or less. A cost seg study identifies and reclassifies building components into those shorter recovery periods. Without the study, your CPA has no engineering basis to claim accelerated deductions.

A full cost segregation report runs 30–100+ pages. It includes an asset-by-asset breakdown of every reclassified component, depreciation schedules by recovery period, the engineering methodology, and IRS compliance documentation. Your CPA uses this report to file your depreciation deductions.

Cost segregation study software varies by firm, but most use proprietary engineering platforms combined with industry-standard cost estimating tools like RSMeans data and Marshall & Swift. These systems help engineers assign accurate replacement costs to individual building components and map them to the correct IRS asset classes. The software matters less than the engineering methodology behind it; a credible firm follows the IRS Audit Technique Guide regardless of the tools used.

No. A standard depreciation analysis assigns the entire building (minus land) to one recovery period, 27.5 or 39 years. A cost segregation study goes further. It breaks the property into individual components and assigns each to the shortest defensible recovery period based on engineering analysis and IRS guidelines.

Yes, but you don't need to limit your search to local firms. Cost segregation is a specialized engineering discipline, and the best firms work with investors nationwide. R.E. Cost Seg serves clients in all 50 states. Property inspections can be conducted through virtual site visits, so geography is rarely a limiting factor. What matters most is the firm's engineering expertise, IRS compliance track record, and turnaround time, not proximity.

Most studies take 2–4 weeks from document submission to final report delivery. Timeline depends on property complexity, how quickly you submit documents, and whether a physical or virtual site visit is needed.

Yes. Many firms now offer a fully online cost segregation study process. At R.E. Cost Seg, the entire engagement, from document submission to engineering analysis to final report delivery, can be completed remotely. Virtual inspections using photos, video walkthroughs, and satellite imagery allow engineers to classify property components without an in-person visit. Online studies are faster, more convenient, and produce IRS-compliant reports identical to traditional on-site studies.

You can try, but the IRS expects your study to follow engineering-based methodology from the Audit Technique Guide. A DIY approach lacks the engineering credentials, component-level detail, and documentation required to survive an audit. For most investors, hiring a qualified firm is the safest and most cost-effective path.

Absolutely. A look-back study lets you claim all missed accelerated depreciation on properties you've owned for years, even a decade or more. Your CPA files Form 3115 (Change in Accounting Method) to catch up on the missed deductions in a single tax year. No amended returns required.