Why would we assume the best case scenario with this type of situation rather than play it by suspicion and keep tabs on the tenant to make sure he does not create a major inconvenience for his neighbors and potentially significant damage to the property?

I was actually just playing with the calculator on BP and came across a land contract deal from Zillow.

He would build then sell the house + lot (it's essentially a loan to him so he has some capital to play with since it appears most of his is currently tied up). - The return has a hefty minimum but can go higher depending on the sale price

I am not sure how much hardball I should play with this. 

I'll be interested to see how this plays out in 15 - 20 years.

I typically see a turn around play that costs around 15-20k per unit in this market, and with that money we can get a nice product that has pretty much everything done on it from the windows, roof, electrical some plumbing all the way to the kitchens and baths. 

One of my favorite episodes (I believe it’s episode 6 or 7) is Why You’re Not Financially Free (or something like that), where he talks about home equity (which plays into your 15 vs 30 question).  

While driving around at work and at jobs I will play BP Podcasts just to surround myself with the material. 

Use a color swap app or a program where you can play with changing the exterior color of the house. 

As for cashflow on 4 plex’s, there’s lots of ways to run those numbers and lots of factors play into typical returns for a property type.