Creative Financing Question

[Patrick Michaels]

I have been speaking with an 8 unit property owner about purchasing their property. They have $100K of debt, but it is worth about $550K. Their loan is not assumable. My question is if it is possible to use traditional financing to buy the property for $100K, then after closing sign a promissory note with the seller for $450K. I had a realtor tell me he had seen this before, but hoping to get some feedback from the BP community about this strategy and any land mines I should be aware of if this is a possibility. I have explored multiple creative financing strategies on this one and none have worked for both of us yet. Thanks!