Typically, these sales are handled just as a normal sale, however Purchase Agreements need bank approval and usually on thier purchase agreement, and that can take anywhere from a few days to months to get an answer back on. The inspection window if there is one is sometimes tightened up, also. I'd get a realtor involved to represent you that has experience in this sort of transaction, for sure. Oh, and these properties are sometimes sold "as-is". Other than that, they are reasonably similar to the typical resale transaction.