Collection agency turnover the case to attorneys rarely only when judgement is large and landlord is willing to pay heavy attorney fee, which can start at around $3000 for filing garnishment but even that doesn't go anywhere without a valid address of the tenant.

Squatters break into vacant homes, can present fake leases, and are a valid problem, but if you have cameras on the house, you will be able to get them out right away and you will see them going in.

That's a very valid concern.

It's been illuminating to see who the valid owner of each property is; there's a landlord leaderboard on the site.The direct value proposition allows lenders to track a list of clients or companies in real time.

They take decent care of the property, but I would get texts all the time telling me to fix many things (some valid, some completely unnecessary) and would get upset if I ever denied any of the requests.

If it is then it is a valid comparison.If it is a 2 bed 2 bath condo, then make sure you look at those comps and not the hotel.

I'm also considering finding a seller that would pay more than me to help my father-in-law out and perhaps get a wholesale commission that I could use on my next (ok, first) brrrr, but I'm not sure the best way to validate a fair price or know what a fair wholesale commission would be.

There's an aboundance of data to validate that case. 

Use services that can validate the authenticity of documents and employment history.Require Detailed Applications: Ensure that the rental application captures comprehensive information, making it harder for fraudulent applicants to provide fake details.Conduct In-Person Interviews: Meeting applicants in person can provide additional insights into the authenticity of their application and allows you to ask follow-up questions based on the details they've provided.Utilize Professional Screening Services: Professional tenant screening services are invaluable for conducting background checks, credit checks, and criminal history checks.

Since this is a rehab, you shouldn't have to worry about offering a builders warranty but here's some things I've become accustomed to doing to make the warranty, sale process and transaction process easier.