Which study do you think has more audit defensibility?

I have been able to review or been told of several audits (from other REI tax colleagues) related to cost segs in the last year or so- and of those none of DIY cost segs were allowed under audit. 

Companies I've found and the cost they would charge for 1 property under 500kKBKG - $450 - (audit support included)Re Cost Seg - $1800 (audit support included)DIY Cost Seg - $495 (+ additional $195 for audit support)Would love feedback to before settling on one.

Does anyone have personal experience with specific scrutiny of a logbook during an audit?

The $1,000 fee is reasonable — it’ll cost you far more if you make mistakes, miss deductions, or get audited later on.

You can (and did) receive generic advice, but it is not enough if your goal is to be audit-proof.Things you may be missing:- before counting hours, you need to pass material participation for each of the activities (or group of activities)- there are two different groupings of activities, and you may need to combine both- targeting 750 hours is very unsafe, you need a significant cushion- driving hours have been treated by courts both ways, so you cannot rely on them to pass the test- a helpful informal way to look at hours: if someone else was performing the tasks that you want to count as REPS hours - would you pay them for these hours?

My accountant wants me to start doing this in the event of an audit being I’m starting larger projects and will be implementing cost segregation Thanks

In the event of an audit, you'd need to prove your passive.Assuming you're passive, then you can buy long term or medium term rentals and do a cost segregation study

You’ve got depreciation recapture, passive activity rules, AMT, and audit risk to manage.

There is no official IRS form so the best practice is to use a simple spreadsheet or tracking app you can update regularly and retain for audit support.