In my experience, there are 2 ways to do this. One is impossible, the other very hard.
If you find a house and then try to find that exact loan for sale, it is impossible.
If you shop for loans that are for sale, find one and then research it and discover the house/deal is right, it can be done. But you need the right situation with willing owners and no junior liens.
The only way the buy the note instead of short sale really works is with bulk.
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