Thanks a lot for replying trys.
I am not really hoping for a professional career as a drummer. Well, I used to, but I have become a little disillusioned and I am studying English and French now at a German university. (not that this is what disillusioned people usually do, haha) But hey, you never know, maybe going to a school like that will strengthen my determination again.
So I am rather planing to do this for a shorter period of time in order to be in an English speaking environment (beneficial to my studies) and, of course, also to improve as a drummer and musician in general.
But I think the fees are still quite moderate compared to the top American drum schools like PIT or Drummers Collective. (I was also thinking about going there) But you sure are right that London is an expensive city.