If the contractor submitted drawings, approved, and permitted, then you could get a copy from the building department, just sweet talk your way to it, check the drawings if it were according to plan.

However, you are competing with another unit in the complex that is 20% larger and only $50 more. 

Neighborhoods such as Ozone Park, Richmond Hill, etc. are good starting points. (2) I'd say the sweet spot is 2-3 units, to limit your net outgoing < $3.5k.

It was a huge complex but we took up 6 apartments so that was a bit of free advertising.  

You are in a sweet position so do things the right way and for the long run it will benefit you way more. 

Sweet!

I think you are making this more complex than it has to be.In addition, yes the due on sale clause is a concern, but as I mentioned, just transfer it back into your name if the bank comes knocking at your door and that should resolve the issue. 

Investing in commercial real estate is a complex process and for a novice investor there may be hurdles to consider.

If they were able to swallow their pride and actually DID take hand-outs, then clearly they didn't have too much pride, now did they...I realize the English language is complex, but hopefully you can figure it out...

This complex has a 75% owner-occupied; and seems to rent quickly.