In reply to steve taylor:
Gold Car are possibly the cheapest at Mallorca airport, but the length of the queue at the airport to pick up your hire car may be inversely proportional to the price.
We went in October and waited for 25 minutes to pick up our Avis car. Meanwhile, the queue for Gold Car looped around the arrivals lounge and I met someone who had waited over 4 hours and was still a distance from the front of the queue when they gave up and tried to get a spot booking at Avis instead. The next cheapest only had a marginally shorter queue.
I'm not sure if it's always like that, but on that day I was quite pleased we'd paid £100 extra.