We need to rent a flat for a few months in the North of Spain but we live in CdS. How can we be sure that the "Owner" is just that etc and not get ripped off with the deposit etc when we can't actually see the property?

When asked we provide copies of utility bills, details of past renters who are happy to oblige.
No owner should object to providing proof of ownership.

That's roughly what I thought of doing, asking for an Endesa bill. We went after a flat, the woman was very forthright asking for reservation deposit etc. Flat looked good but photos V small and everything done with sms, We asked yesterday am. if she would do everything by email and she replied yes. We haven't heard anymore from her since 9 am yesterday..............