Hi all,
Lot's of really good responses so thanks a lot for everyone who answered.
Just a couple of things to add:
A lot of people are saying that actually when you work out all the costs, it's just as cheap to hire per hour. That may be the case but once I have my PPL I might want to fly for example to Scotland, and then stay a few days. How could I possibly do this with a rental aircraft unless there's some kind of hire car style thing where you just drop the aircraft off.
Also in response to the idea that I won't know what type of aircraft until I know what type of flying I would like to do, the idea was to buy a plane that is safe and cheap to learn in that's the only thing I need to worry about for now. Then some time after PPL I would probably sell and upgrade.
I wouldn't be rushing into buying something without having a qualified aircraft mechanic check the thing over in detail. The idea was to add that as an initial cost which I presume would save me a lot of money considering I have no idea what to look for in terms of potential problems.
I'm still thinking about it despite some of the people saying NO NO NO DON'T DO IT, that's if I could even raise the cash. For now I'm going to start learning anyway, too excited to wait. Now just to overcome air sickness.......