Also don't be concerned about the 2% rule or the 1% rule or any other rules. 

- Since I already own 1 other rental property that I purchased last year (not including the one I'm selling), I'm concerned about getting financing on 2 other properties, which could total up to $700k in value if I was putting 20% down (the $140k).   

If this is your first investment property and you don't have local market experience, I would be extremely careful.

Only reason I could come up with is seller concerns about financing falling out.

In many areas, where it's zoned for one family, there would be extreme opposition to higher density zoning, usually it's voted down.

Again, treat this scenario with extreme caution.

I'm concerned that if I tell him not to be smoking then he is just going to try and hide it by smoking inside and really causing damage to the unit. 

But also @Linda D. makes an extremely good point, in the mean time, stay extremely engaged in surrounding yourself with like minded REI individuals as this will continually remind you and motivate you to stay accountable to your WHY you are doing this. 

Batteries are getting better, however for now I would only suggest them to very concerned "doomsday" folks or for the intent of reducing time-of-us utility charges.

I am mostly concerned about a visually respectable way to show the division in the two lots.