Common sense tells me his attorney has no great incentive to try and screw you out of anything being friends, that would or could hurt the friendship and fall back on him.

That is not a common configuration. 

While I guess it is possible to build a unit and not install ceiling fans, they are so common that not including one would be a negative in most renters mind.In my market, things like central air & heat, dishwasher, washer/dryer are amenities.I have never had a call regarding a ceiling fan from a tenant, but have had to replace one (1) during a unit turnover, as it was just too loud for my taste, but it was very old (~15yrs).

Quitclaim deeds are a very common type of legal document that deals with the rights associated with a property.

Is it best to offer a "subject to" type transaction to the homeowner, catch up her payments, and assign/rent/wrap/etc if the home doesn't meat the common 70-75% ARV minus repairs?

As a residence, that won't appraise out, (1.) there is too much value in the greenhouse attached than to the residence (2.) won't be getting a market approach on a 1 bedroom or with the greenhouse (3.) it's not common for the area (4.) the highest and best use probably isn't residential (5.) marketing time on an appraisal can't be established......there is just a list of appraisal aspects with non-conforming properties. 

Common entrances should be locked. 

Common strategies to take advantage of first-time buyer perks are  to invest in a duplex and live in one unit or house hack - buy as primary, fix up and rent out.  

I know house hacking with an FHA loan is a common first step into REI (my current strategy), but if there are other low cost options that you guys think would work, I'd be more than willing to try them out.

.,  Consolidation like you're considering is becoming increasingly common.