I'm under contract for a nice double and was hoping to use part of the money for my portion of the down payment.

if you need $200K for a project, no one is going to loan you $200K - you need a down payment, holding costs, and you need to know what you're doing or you'll just turn that $200K into $150K.good luck

He was playing nice, but then started to really press me about the final payment which was a large sum of money.

The current owner is letting me take over the property as a tenant as long as I pay the water bill and the mortgage payment on it and whenever I decide I can purchase property for the balance of the mortgage  they are in no hurry for me to purchase the home as long as the mortgage is paid. 

Here is what one of the new people I coach from Socal did with a property in Phoenix
I helped him find. He has taken his training seriously. It’s a Subto (Subject To) that I helped him buy “off market” and he chose t...

Although you have to wait for payment with a 203K loan. 

Would you buy 5 houses in Clarksville, which rent for less than your mortgage payment? 

THE NUMBERS: With a purchase price of $7M, my Investors and I put down $2.7M as the down payment on the property.

It looks like according to the county site (sbcounty.gov) they require all renter payment go to the active owner. 

Could you kindly suggest the best resources or methods to identify comparable properties in the area?