Most of them will still rent you a car if you go to their desk in the arrivals hall at the airport. However, if you don't have a valid credit card, they require a substantial cash deposit.

Record Rent-a-Car once asked us for 500 euros in cash because my Visa card had expired a few days earlier (my new card was still at home !).

I regularly use my Visa debit card with Record and Europcar plus others without any problem.Maybe its because Im a regular reliable customer.Try it first and have a credit card for backup.

most will except cash as already said,but a card is a lot easier

try http://www.carhire4malaga.com. we hired through this site and i am sure we just left a deposit with debit card.