Even then I want to isolate the risks as much as possible between the assets.

Isolate work areas from living areas with plastic sheeting.

A vacant inherited house, by itself, is a sleepy list unless you are sufficiently skilled to isolate and stimulate their pain.You need better lists which target people with big, in-their-face problems. 

IF you know how we could find or better tune our search to isolate builders that would be wonderful!

To make a long story short: Our tenants reported that the main circuit breaker has been tripping with some frequency, so we brought an electrician out today.He isolated the problem: romex wiring outside the house going to the central A/C unit.

HUD does not isolate and identify any issues

(not sure if this works since I'm not 'pro') - BP rental calc has it avg $4,680/yr (for 1100 rent), even though I put the same exact numbers/expenses, etc as in my spreadsheet...not sure what I'm missing or how that number is really calculated4-Plex:Expected Purchase Price: 250kUnits: 4 (MFH)This is a recently rehabbed building, so no other upfront costs neededAll units are rented at 850 per unit, per month = 3,400/month (supposedly there is a wait list too, which I will be sent tomorrow)Location is not the greatest (no crime issues, just in a more isolated location.

If we isolate each additional bedroom past 4 and look at the bedroom ROI in a vacuum that's a 96% return, or 2,000 % Cash on Cash (house hacking with 5% down) for each additional bedroom past 4 you can find / create in a single family home.

The home was ~30 miles from a hospital, isolated on 3 acres.

I only ask because if this was one isolated incident, it is possible their offer was better up front, but negotiations dropped it back down.