Take a hard look at what you are bringing to the table here. 

I also include furniture for the common areas such as a couple of basic sofas, a wall mounted television, dining table and chairs and other odds and ends.

Between child costs, debt, and just the cost of living, I can barely put food on the table.

Our group does underwriting as a service for various sized investors across asset classes.

what size project? 

Exterior doors sizes (12x12; 12x14; 14x14) and mechanisms (chain, remote)? 

It might sound ridiculous to pay these people just to go look at a place, but until you have a decent size portfolio and a team you've used time and time again it might be the only way to get a deal done.

We choose this particular one because the neighborhood is perfectly set up for it & already had existing STR's in it, the layout & size were ideal & the private pool is not just out your living room door but is actually private as no one is behind us & the sides are walled off which we thought the additional privacy would make it more attractive.

Any reasonable allocation method is fine.We usually use square footage to allocate basis if there are different units, but per unit might be fine if there are a lot of units and they are all roughly the same size, give or take. 

If you plan on holding onto that property for the next ten years and content with the size of your portfolio, then you may be better off to not do the refinance.