I would go for the JAR license, unless, as said earlier, you have an issue with the medical. It's unlikely you will complete in the minimum hours that the NPPL talks about, and to pay the extra and then end up with only an NPPL would be annoying!
As for books etc., I guess it depends on your club. Mine didn't mark them up, but loads of things I had to buy from Transair anyway as they didn't stock them.
Definitely buy rather than borrow the books - I still look at them quite a bit now although I have my PPL