If you *do* come and stay in London, make sure you pop round and say hi! And definitely come along to church with us.
It's a fantastic city to live in in lots of ways - loads of culture / history / things to do / eat. It can also be quite a lonely city if you don't know many people, because it's so huge and anonymous - so getting stuck into a good church community to support you is really important.
I imagine you will find it quite expensive - though I don't know exactly what the comparison is. But a decent meal out could easily cost you 15 GBP - and you can ask Google what that translates to for you (mind you, McDonalds is probably about 4 GBP, which is obviously a lot less!). In my experience, a *cheap* rent would probably be of the order of 360 GBP per month - but that can vary massively based on which area of London you're in, and if you share with lots of other people you could get something cheaper (but realistically you'll probably pay more than that - cheapest I ever paid was 450 per month and that was through my church)
Hope that's vaguely helpful! Generally I love London, and think it's great! You just need to make sure you can actually afford to survive!