I recommend starting with understanding and breaking down the numbers....what your model/strategy will be, what you can qualify for, and how that all translates to the current marketplace. 

I have worked in restaurants as a server for years and love the hospitality industry and would love to translate that into Airbnb.

The fact only a partial interest was being pledged should have been clear in the deed of trust which should have translated into the deed you received explicitly saying it was only for a partial interest.

Now those % don't necessarily translate exactly over.

This translated into a full-gut of the entire house with an estimate of just under $40,000.00 for the abatement.The Vendor, an estate, was unwilling to do the work (expected) but were equally unwilling to reduce the price sufficiently for us to underwrite the risk.

While not PCB, I'm sure some of my experience could translate to your area. 

Many companies touted the add on value as simple math where the energy savings translated to extra value equal to the cost of the system.

To quote Pitbull, who was translating a Spanish proverb, "Ask for money, get advice.

From an NOI perspective, the delta is $5,400 in year 1 which, at a 6CAP, translates to a decrease in value of $90,000. 

There's lower fees as they have the mortgage broker do a lot of the work who gets paid at the end of the transaction so the lender doesn't have to pay the mortgage broker a salary or benefits which helps lenders keep costs down which translates to lower rates and fees.