You can submit your offer and in the financial section you have a choice as to what kind of financing you will choose. You will choose cash and then submit your offer. You have to keep calling the bank over and over and over again. It can be quite frustrating! I don't think your offer will be any stronger if it is cash or not.. but you never know. You should just stay on top of the bank by calling and telling them about your cash offer. They may just ignore you but it's worth a shot!