I hired a car from them for 5 days March 30-April 3 and I only used less than half a tank of diesel.  I know they don't refund on 5 day rentals but it's a total rip-off.  Why can't you bring back full like in other countries.  Everytime we hire a car the rental company wins - it's never empty :( 

When I got the quote from an agency the rental cost was €89 and by the time i'd paid for the diesel and extra driver and insurance it was over €240 :-/ Talking about sharp practices - they're worse than Ryanair for extra charges.  I will think long and hard before using them again.