LOOKS LIKE A KILLER REO DEAL BUT WHAT ABOUT PREQUAL?

Hi I just stumbled on what may be a killer REO deal. The listing price for the home is $199K with the FMV for the area around $280 on the low side to mid 300K's. I will be looking at the home tommorrow which I am sure needs plenty of work but the listing agent requires a proof of prequalified funds to be given with all offers to the bank. The problem is I have not been prequlaified as of yet and I am not sure If I even will. Am I wasting my time here without that? Will the bank realistically consider a offer thats not cash? I would expect this home may get alot of action. Please advise. I would hate to miss this possible killer deal. Thanks