In reply to gammarus:
We went for Auto Europe Car Hire. Initially a little confusing when we arrived as their office is not at the airport but they provide a short shuttle from the airport to the car hire office.
We went for the cheapest option and had a little fiat 500 for 2 weeks, think it cost about £70 in total!
No problems on return and was happy with the service.
If you hire cars a lot I would recommend taking out excess insurance. I got an annual policy for £40 with icarhireinsurance. Just means you don't get stung with extra costs for excess insurance when picking up the car.
Hope you have a good time.