Relating to a similar thread about getting from airports, if you're going to any of these 3 cities check out the way2stay.com website on this link: www.way2stay.com
It's got weather reports, airport transfer and cultural info for Barcelona, Amsterdam and Paris, as well as its pretty extensive range of vacation/corporate apartments.

If you aren't familiar with these cities, the area map and guide provides a good sound description of each and every district, including a beach guide for Barcelona