There's a law that every state has called "statute of frauds" that requires some kinds of contracts to be in writing, and they can't be oral. One of those kinds of contacts is contracts to sell real estate. Another is a contract that can't be performed within a year. This contract may be both of those.
These restrictions are because real estate is unique, and it's usually very expensive. The 1 year rule is because people's memories are bad do it's too risky to rely on oral contracts.
There are wrinkles and exceptions to these kinds of contracts too, like when they're partially performed and there's reliance and a change of postition by a party seeking to enforce an oral contract.
So all this means is that you need to see a business lawyer to do over all the details, because there's no simple answer.
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Attorney Koslyn is correct, MT has a statute of frauds requiring a writing for real estate deals. Even a lease for longer than one year requires a writing. You have done a poor job of pretending to be a realtor or landlord. And it is not clear which. You now need to see a lawyer to sort out the situation as soon as possible. Anything to do with real estate, even a rental, should be in writing.
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