I’d agree with DataAgent, except…the way you worded the question leaves some wiggle room. It also depends on whether both sides want there to be a contract. If they do, whatever the flaw, it can be remedied.
If the buyer (or seller for that matter) wants to void the contract, it depends on what “wasn’t fully signed off” means. If the seller never signed, it’s not a contract.
If the seller forgot to initial one page, it probably is. (I haven’t looked at a residential sales agreement for awhile, and I don’t think there’s a clause requiring initials on all pages in order for the contract to be binding. State law does not require it. Initials protect the counter-party, not the initialer.) I’m sure there are other minor flaws like that, which wouldn’t necessarily make the contract void or voidable.
