By cash, I am assuming they would take a cashier's check (bank check)? These are made out to the specific seller, but you typically would not go to the bank to get a cashier's check until after you had tried out the machine and made a verbal agreement with the seller. I personally would never bring $4,000 in cash anywhere. My assumption was that "$4,000 in cash" simply means they do not want to take a personal check.