Back in the dark ages ('80's) I would approach older home owners & offer them a buyout with them holding the note at an attractive interest rate. My neighbors at the time were an amazing older couple who were RE agents & they would know who was interested in selling.
Sometimes a down pmt was needed, hence partnering with others. Interest rates at the time were running 18-19% but capturing a beautiful old tired home that would appraise much higher after rehab was my exit strategy. I would pay off the sellers note (some with a penalty) once I got more reasonable conv. financing. It paid off very nicely & the majority became rentals or were eventually sold to buy more. I kick myself for the ones I let get away. One was offered to me for $110,00 & just sold for $590k.