A deal is a deal, but it helps if you have someone in mind when you contract it. 

I have a contract on a house in Phoenix AZ with a value of $500,000 and a mortgage of $288,000 to be taken subto.

Utilities are OFTEN overlooked so reach out to power, telecom, gas (or go all electric), water, and sewer to make sure you understand what it would take to get separately metered services from the primary house.

I can't buy gas with a percentage.

If you are a doctor with proven income or a contract, the bank makes incredible deals that they wouldn't make for me. 

Oh, one more thing to be wary of, section 8 contracts states that if you have long running issue and not fixing it, not only can they stop the rent payment for that unit, but for every unit in that property.and another one. 

As used in this Section 18, "Interest in the Property" means any legal or beneficial interest in the Property, including, but not limited to, those beneficial intereststransferred in a bond for deed, contract for deed, installment sales contract or escrow agreement, the intent of which is the transfer of title by Borrower at a future date to purchaser.If all or any part of the Property or any Interest in the Property is sold or transferred

Not that it really matters.No institutional lender will give someone a loan that doesn't have:1) Credit history2) A social security number3) Income3) Employment historyYou'll want to research Wholesaling and Land Contracts.

I got it into contract and then had a huge plumbing failure during the home inspection.

I am a general contractor that specializes in kitchen remodels and high end custom cabinetry, but I'd like to use this project to pivot into more general contracting and property development.