For those Renting a property in Spain, you should never pay your last month's rent.  You should use your deposit to pay the last rental payment.  And if your landlord asked for 2 months as a security deposit, you don't pay the last 2 month's rent.  Do this no matter what your contract says.

The reason I am advising this is because you are very unlikely to ever get your deposit back.  In Spain, tenants don't have the protections that are in place in countries such as the UK, so landlords can basically can do what they want with your deposit.  Yes, you could take legal action against your landlord but this is likely to take years and years and years under Spain's third world legal system.  So it is a waste of time suing your landlord and he/she knows that.  It does work the other way though.  The landlord is very unlikely to chase you for breach of contract for the same reason.

I know a lot of people who have been rippedd off in this way by lanlords and letting agents.  Most of them were expats who didn't really know how things work out here.  This has just happened to a number of people I work with, who haven't been in Spain very long.  They naively think they will be getting their rental deposit back.  I've prepared them for the worst...