Acceptable amount under FMV of Rent-IRSFixer, Maybe, Anyone

[taxea]

This was prompted by Erchess' recent post and something I have been wondering for a long time.
Does anyone have any documentation that indicates how much % under FMV the IRS will accept before looking at a rental as personal use? Is there any amount that is acceptable? How does the IRS determine FMV of rentals?

I have Googled til the cows come home and havent found anything on this issue.

[joanmcq]

I've used rentometer.com before to determine if a rent was reasonable. There really isn't a hard & fast rule; in audit a lot of factors can come into play: the condition of the property, how long the tenants have rented the place, is it a house or a duplex, or an apartment, etc. Sometimes neighborhoods can differ by a block; for example in my neighborhood, one major street separates 'nice' from 'da hood'. Is it on a quiet or busy street? Facts & circumstances......you use what you can to support your position.

[taxea]

sorry Joan didn't realize I posted the question twice but thanks for you responses.