try ur state board of realtor’s www or go to a local title co. and ask: “I need to sell my home as a FSBO. what paperwork do i need?” they will tell u or give u what u need. all u will need to do is add a line that states u r purchasing subject to the existing financing, and that the deal is contingent on ur partner’s approval. then take it to an attorney familiar with creative real estate investing, and even better if they are familiar w/sub 2. have them look it over for state specific info and to make sure it’s enforcabel in WA if need be. then u r good to go. don’t do anything w/o an attorney on ur team.