Disclaimer: I am not a tax professional. Please consult your tax professional for the definitive answer to your questions concerning Cost Segregation Studies or any other subject discussed below. As with most every tax question the best specialist will tell you, “It depends.” That is true of what you will find below but since EVERY situation for EVERY taxpayer cannot be covered here, just consider what you read as food for thought to discuss with YOUR tax professional. (That last part was added to keep people from answering back with things like, "Yeah…but if I am a foreign national and my birthday is before 1959 and my favorite color is blue I can still take the depreciation 
Andriy,
You know the saying, “The devil is in the details?” Well, this definitely applies to Cost Segregation studies and depreciation. Here are some of the “details” I have seen.
Detail: If you are not considered a “Real Estate Professional” (this is an IRS designation that has specific requirements…not just the checking of a box that says Real Estate Professional on your tax forms), then the amount of depreciation you can take is very limited ($25,000). So even if a cost segregation study gives you $100,000 of depreciation, you can only take $25,000 of it if you don’t qualify as a Real Estate Professional. (The actual qualification is complicated enough for another post of its own but is often unknown to new investors).
Detail: Again, without qualifying for Real Estate Professional status, even how much of that $25,000 that IS allowed phases out with your income. If you have over $100,000 in income the amount of depreciation you can take starts to be less and less, (these are Passive activity loss rules). Once your income reaches $150,000 your ability to claim depreciation deduction is completely eliminated.
Detail: 1st year bonus depreciation is going to start phasing out in 2023 and, unless changed in new tax law, will be completely eliminated by 1 January 2027. (Again, unless Congress extends it).
The 100% bonus depreciation amount remains in effect from September 27, 2017 until January 1, 2023.
After that first-year bonus depreciation goes down as follows:
- 80% for property placed in service after December 31, 2022 and before January 1, 2024.
- 60% for property placed in service after December 31, 2023 and before January 1, 2025.
- 40% for property placed in service after December 31, 2024 and before January1, 2026.
- 20% for property placed in service after December 31, 2025 and before January 1, 2027.
(Yes, there is overlap in the years…talk to your tax professional about what you can take and when).
Detail: Depreciation is often considered to be analogous to a “loan” from the IRS. In other words, you can take depreciation but you will eventually have to pay it back (depreciation recapture tax). Doing a 1031 is analogous to an extension on that loan. However, to eliminate having to ever pay that loan back you have the pleasure of dying and then your heirs get a “stepped up basis” on the property (wiping the “loan” off the books). (Note: Stepped Up Basis, along with 1031’s were recently two of the incredible tax breaks attacked by the legislature. At this time they are considered safe, as is the holding of “accredited investor only” type investments in your Self Directed IRA).
Other thoughts/rules of thumb I have seen;
If the property value is less than 500k it probably would not be worth hiring a firm to do a cost segregation study.
Cost segregation studies, done correctly, by a professional firm hiring engineers to do the study will be your strongest protection against having the depreciation questioned/disallowed by the IRS.
And, I hate to say it, and many will probably argue but, if you have a valuable community and you are a Real Estate Professional I would not do a cost segregation study by myself. I would hire a professional. I would be happy to recommend one if anyone is interested you can DM me.
Hope this helps, if it only confused you more you can DM me or write here and I’ll try to answer to send you to a professional who can.
Capt Sam.