I would tend to agree with the other CPAs typically.The 500-hour test is one of seven material participation tests used by the IRS to determine if a taxpayer is actively involved in a trade, business, or rental activity. 

Since they needed renovations, he invested roughly $30,000 per property to make them rent-ready—bringing his total investment to $110,000 per unit.Once rented, he quickly encountered issues: non-payment, eviction filings, constant repairs, and tenant-related damages.

I was involved in two small infill developments in Michigan (about 15 houses in total) so two very small parcels. 

You could also try looking up money judgements filed against local businesses at the magistrate level and target them with direct mail or driving for dollars. 

Quote from @Theresa Harris: Tell the tenant to phone the police and file a noise complaint. 

I'm in a team who does these deals and we have a team of "door knockers" who go back weekly till the auction, they file bankruptcy which only delays 3+/- months 100% chance that the lender will as that their mortgage is removed from the bankruptcy they file NOD yet again.   

The guy has already stated that he doesn't live there so that alone proves that he knows that was never the intended use (is their a police report or statement for your file?).

So in the FWIW file what I see all the time is those trying to start out and getting the same returns as those with a lot of experience. you need to build your experience bucket and as you make your partners money U can adjust profit splits.. other wise I suspect nothing will happen unless of course you can tap your warm market that will do this because they like you.

However, in emergencies or cases involving health and safety, we would attempt to contact the owner first and, if unsuccessful, proceed with the repair as outlined in the contract.Regarding the hot water heater, do you know if it genuinely needed to be replaced?

I know because I was involved in it with O.C..