How much more expensive is living in London than M

[tanviralikhan]

If I lived in Manchester but was offered a job in London, I'm wondering what sort of pay rise I should be looking for in order to be better off? London weighting in the public sector seems to be around 3-4k per annum, so say if I was on 25k in Manchester should a 30k salary in London be good enough to make it worth my while?

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