If I could rent a reliable plane in Spain for 100 Euros, it would also be great news, and it would be unrealistic. The UK and Spain are two different markets. By asking for "cheap" you are not starting out a mutually respectful business arrangement, what service provider wants to be thought of as cheap? Certainly not the one who provides a reliable service!
I suggest that if you would like to economize on a reliable service, you inquire about a block time arrangement, a "volume" purchase, so to speak.