Making the sale with a Contract for Deed, then sell the Contract for Deed

Does anyone have experience marketing a home with seller financing and having someone lined up to buy the Contract for Deed or mortgage immediatly after closing?  Sellers have a real advantage right now if they can offer seller financing however many can't because they need the money to pay off their mortgage and buy another home.  But what if you had someone lined up to buy the financing.  Is anyone doing this?  Are their companies you've worked with who buy Contract for Deeds or other types of seller financing?