I also use doyouspain but have excess insurance in UK so now dont take their insurance. If you take the insurance on booking then on collection the car rentals tell you that its the brokers insurance and you need to take their insurance so just be aware as you could pay twice!
I also try to use the same company which I have found really helpful when choosing the car. Click and Rent are off airport and the shuttle bus is easy enough. They close early so just be aware.
Choose full full so you fill up what you use.
Good luck!