We rented a 4 x 4 from Barcelona airport. The shuttle to take us to the hire building was waiting for us when we arrived. The staff were friendly, however being charged extra for driving the vehicle to Andorra and getting charged over 1000 euros deposit was a little annoying. We had no issues with the car whilst using it and got the deposit back within the next day or so of returning. Having had trouble with Sixt on every occasion (3 times) at Barcelona airport, we were apprehensive about using Autoclick, but it was refreshing to have no issues