Basically the house is finished it just needs the flooring, hvac and power supply and structural final.

However, as you know, a passive investor in a real estate syndication one must always maintain influence over the decision making and management process through the power of veto should things not go as originally planned.  

Smart locks are great until wifi or power goes out and the renter is pissed that they can't get back into the unit

Get him Power of Attorney and quitclaim back to her maybe.

I also have a wife who is in general extremely skeptical about anything REI-related, but at the same time, she understands its power as an investment vehicle.

You (the partial buyer) then collect 60 months of payments, and starting in month 61 the payments revert back to the original seller of the note who owns the back end.This is a powerful strategy which can be very beneficial to both the seller and the buyer for many reasons, such as:- Allows the seller to recapitalize some of their investment or raise needed cash without selling the entire note- Allows the partial buyer to get into the note for a much lower cost

The Due Diligence PeriodOne of the stipulations in the contract is that water and power must be turned on before the due diligence period starts ( the house was vacant).

Tore out carpets and finished hard woods, painted entire house (interior), power washed What was the outcome?

More power to  you.

Whatever you do, don't seek self help and try to shut off power, remove doors, etc.