As for vetting them you may want to use @Steve Rozenberg`s exhaustive checklist as I think it covers everything.

I have exhaustively searched for additional financing with no luck.

Eat in your car, take a different route to and from work, drive until you are exhausted and then do it again tomorrow.

Now I have the property ready and exhausted and need a good short term rental contract. 

Are there other, more detailed or exhaustive resources for this?

Once you've exhausted that avenue or if you don't qualify for one of the myriad reasons people don't qualify, go with a portfolio loan.  

It gives additional Liability coverage if the limits of your homeowners or auto policy is exhausted. 

We always recommend that borrowers exhaust the conventional financing options first because the money is cheaper and the terms are better. 

For the most part, there is no income verification (although you'll need the operating income statement and the leases for the property).The first choice should be local banks and credit unions, then conventional/commercial lenders for loans over a million, but if you've exhausted those options, a portfolio lender will be able to help. 

Since you've owned that property for so long you've exhausted the depreciation allowance and your basis is probably close to zero.