This seems a little suspicious. However, it would all depend upon the terms of the land contract, whether it has been assigned, and what are the terms of the assignment. Without knowing the contents of these documents, it is difficult to answer your question (although you did the right thing in not posting any specific information to this site). You should have a lawyer review these documents and the summary he sent you to make sure you are protected. Let me know if I can be of any assistance.
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