Petra, I'm going to London too and I can tell you that I have spent a totally undecent amount of money to go to Munich and Dusseldorf and to go to London... So don't feel bad, you're not the only one... Some are even coming from the US or Japan to go see him so you see...
Regarding accomodation in London I'm already staying at the Griffin House with some of the MFCers but I'm sure that some are still looking for something...