@Michael Dallas this sounds like it could either be a great deal or a suckers bet, and unfortunately, it's impossible for any of us to tell.

Odds are, that scope of work is not a part of his original contract, so he has no obligation to do the drawings for you. 

A drain pan is for emergency leaks from the washer, I would bet 90% of households don't have one (I don't).

The deal is just too odd and risky to pursue for me. 

In fact, I would bet that 99.9% of all wholesalers could spend the some number of hours working at McDonalds and they would make more money.I recommend you focus on the house hack.

My easiest and safest bet would be to just build the outside storage lot.

It's all I really need in a CCW and with it being small and light, odds are good I'll always find it easy to carry. 

Bet you know who that is don't ya Carlos? 

FB Marketplace is probably your best bet - You can try craigslist too but at least with FB you can do a quick scan of someone's profile before talking to them. 

While doing an Airbnb seems like a good idea it does not resolve the issue of the divorce and splitting the propertyI still think your best bet is to drop the price and sell it and start your life over.