Is the unit permited by th emunicpality as a habitable unit.

I have an odd question; If you hadn't been in a position to do the rehab immediately, was it safe/habitable enough to rent "as is" with only minor work/cleaning, and if so, what would the cash-flow have been?

Ultimately you will be in a short term loan so your planning is vital. 

The attorney can draft the note for you, but it is vital to know what clauses you want to be included in the note.

I've given up a few pieces during the contract phase but I don't make that a habit. :)

I do believe finding partners that lived through the last cycle is vital because when the going gets tough, the flakey will bail, but those that have lived through it will be able to weather the cycle but also pick up on the opportunities left by those that throw up their hands and run.

So besides all the basic needs that a house requires to be habitable from drywall, cabinets, roof, etc. what other repairs are needed?

Uninformed investors often buy loans with vital originals documents missing.  

Good communication is already vital to a relationship and will be important here.

It's just vital to vet them out and find out if their legit or not.