I neglected to mention that I also took out an excess insurance cover with www.insurance4carhire.com at a cost of £49 for annual European rental, useful if you are travelling and renting often and the policy covers the Excess on theft,damage,, windows,tyres,undercarriage and roof and supplements LDW/CDW which is normally included.
From what I gather you pay any excesses locally then reclaim with 30 days. It is the policyholder that is insured, not the vehicle so you can decline the rental comany's excess insurance at the counter.
From experience most of the online agents such as carjet and cartrawler, doyouspain all use local companies such as Centauro, Goldcar, Solmar etc based at Murcia terminal so you should have no probs, they obviously negotiate rates. I think Victoria's office is in carpark straight outside the terminal, so very handy. Certainly on this occasion Victoria was best deal.
I think all companies charge for full tank and ask for empty return unless under 4 days hire, understandably their charge is higher than self fill.
The desks all get busy as normally a few planes arrive together so worth letting the wife collect the heavy bags whilst you queue at the desk
. as it is before customs for what they are worth.