Where did you live exactly for £700?
The 1500 I've stated would include council tax all bills and travel into work, which is something I would account for as work-based living expenses.
When I was a poor grad I was sharing in Camden for 700 per month in a house full of people. Good bunch but it was never a home.
I seem to be only one being realistic in this place.
I like the advise from dowie. Don't get mugged off, London is a much more fluid market than the regions. If you move here you should get compensated accordingly.. It's very very expensive.
Crystal Palace, Dulwich and Putney. You are being realistic if you want to live very well.
If you want to live in London you can do so for a lot less. Don't get me wrong I wouldn't want to go back to earning £30k and live in London, but it is more than easy to do. Still was able to go to the butchers, and go on holiday, and stay at the gym, you just have to be a bit more careful with your budgeting and sacrifice a few things. You learn to be more savvy, get deals, speak to people and get discounts. Easily done. But I'm a confident person that doesn't mind asking for discounts or being "cheeky".
I did however suggest he should ask for relocation costs in my previous post.
But sweeping statements like you need to earn £60k to live in London is pretty daft.
Sure you won't live in a massive place, you won't necessarily be able to fly first class, or dine in Michelin starred restaurants once a month as some of us enjoy, or own a car - but a lot of these things are just luxuries.
Having a roof over your head, paying bills, and buying food, and having some disposable income is completely achievable on more modest incomes.
You've skewed your perceptions owing to what you're earning and the lifestyle you are now living. I could easily say you need more than £50k to live well in London as well, but the fact of the matter is you don't.
ANYWAY all this is irrelevant to the OP, as has been suggested he should see what the equivalent role is being paid and ask for a commensurate salary not only for the move but to add a bit of London weighting so as to not adversely affect the move (it costs money to move after all!).