Well after hours checking out companies etc...... discount codes ,cash back sites etc reviews from others, I have booked through Economy car hire, and car hirer is Centrauro cost for 11 days with discount code was £79.00 but I will get stung with the full /empty Conn >:(, and cost for tank of petrol between  60-140 euros, as it,s only a 2 door fiesta (not cheapest option) I would hope they will charge around 75-85 euros for the fuel, around 20-30 euro ripp off on the cost of the  fuel, I had a corsa in Feb and it cost me 56 euros to fill up but  how much has the cost of petrol gone up since then LOL!!!!!!!!
I could have got a cheaper price through ecarz £69.95 but with these excess charges of £350 for a replacement mirror ,£500 for minor damage,£250 a Tyre or take  the extra CDW @ £ 54 .00 on top of original price  I dare not take risk, whereas Economy car hire there is no excess etc... no ripp off 0871 10p min phone numbers etc... and you get to know who your hiring from.
I now cannot find any car hire firm, operating from El prat that are not using the full to empty conn, if you go through Europe car they state on there site, full to full, yet I read a review today on a site that yesterday a hirer was charged  full to empty and Budget etc.. are the same and cost for a basic panda etc... around £120+
So there  :-/ finger crossed I have done all I can, hopefully it  cannot be as bad a experience as February will have to see ?
Still not got a room booked,  thats my next task, this is looking like £40 + more,than same amount of night,s in February (tortosa Parc) so I might end up a extra night in my tent ;D
I hope this post might help
Phil
PS, I still love My finca and Spain  ;D