Help me come up with a good deal

[James Isaacs]

Seller finance deal. Property is worth 510k and the owner is selling for 450k I want to put down 20K. Seller owes 300k on the property and would prefer an all cash deal if it lets him walk away with 150k. His monthly PITI is $2890 combined condo fee of $750 combined taxes of $375 and I would have my property manager run it at a cost to me of $495. The units rent for $1650 a piece ($4860) please help me come up with a good deal