Owners Direct Barcelona
A useful site to visit is you are looking for self catering accommodation in Barcelona with a big list of holiday homes and apartments is Owners Direct.
OwnersDirect.co.uk does what it says in its name- you won´t be able to make a reservation online, but it will give you a big choice of flats that owners have decided to offer for short term rental. (Similar to Holiday Rentals Barcelona). OwnersDirect.co.uk is more of a directory- you will have to contact the owners and arrange payment later, but the design of the site is well laid out with information clearly displayed on prices, rental periods, details of accommodation, location, changeover day, etc. You can also check the availabilty if the owners have opted in for this service. This site was the original AirBnB.