Our recent trip to Spain was generally good and we saw and did all that we had planned, BUT. Our first taxi ride from MAD to our hotel, after midnight, included the airport supplement twice. The driver simply lied to us, and since the expected transfer service did not arrive, and we were tired, we were caught out.
In Barcelona, beware of this theft technique. You suddenly realize that your face and clothes are splashed with apparent bird droppings. Someone comes forward to help you clean up and you eventually lose your purse.
Crime in general seems to be an issue in Spain and if they plan to make a successful bid to host the 2016 Olynmpics, they had better clean up their act.