In your state, an agreement to sell real estate *must* be in writing or else it void--that is, unenforceable--under the Statute of Frauds (as it is commonly known), fround in the Oregon Revised Statutes at 41.580. Your oral agreement to purchase a home is therefore invalid and unenforceable against the seller. As such, the seller may treat you as a renter/tenant and take whatever legal actions against you he may take against a tenant under these circumstances.