Again, whether it is PERSONAL or a BANK LOAN makes no difference.
The question is whether there is some security interest (lien, mortgage, etc...) on the property, then yes they can foreclose on it if you don't pay. You can attempt to negotiate credit for what you've already paid.
If they do foreclose, you will get a refund between the foreclosure price and what you owe (though often the only bidder is the guy who is foreclosing and he only bids what he is owed).