One-day rentals can be expensive at the major companies because the good promo codes never seem to work well on them. Payless for $19 is pretty tough to beat.

My two cents: I've gotten good deals at National in the past. The Emerald Aisle is right across the street from baggage claim and is very efficient. I'm a big Hertz fan in most locations, but they are inefficient in Tampa: no true #1 Club Gold service. They are next to National, but you have to stand in line for a car. And for a one-day rental, Hertz is rarely cheapest.