We live in Lancashire, I have family in London and my brother seriously considered several jobs there but I honestly don't believe that any inflated salary justifies the living costs. Out of interest what percentage of income is spent on the rent/mortgage?? Our mortgage is about 1/6th of overall income. There are other major cities around the UK that offer very attractive salaries where housing is more affordable. I do appreciate that not everyone can move though. We have a 4 bed detached house with gardens and have 2 other properties that we rent out too and charge £450 per month
I agree with you in a way. To answer your question, my OH is self employed and doesn't always earn the same each month so a bit hard to gauge. I suppose the rent is about 1/6th of our total income too, based on his earnings for the last year and my salary.
Regarding salaries in other cities, I think this really depends on your field. For example, I work for the NHS and I get £6200 per year London weighting (so an extra 500 a month compared to what I would be on outside of London), although even this is a bit misleading as SIL does the same job as me in a northern city and is actually on a band below me too. We do virtually the same job but I earn £12000 a year more than her, other colleagues that I meet from conferences etc who are doing similar work to me at hospitals outside of London seem to frequently be on the band (grade) below me and then less the London weighting too.
Though my OH is now self employed and we could move anywhere (and have been considering a possible relocation to Yorkshire) he previously worked for a city bank and could not have done his job outside of London. A lot of the big international banks only have an office in London.
If I was in a relationship with someone else in the NHS earning the same as me, we would possibly be £24000 a year better off in London than out. After tax I think that difference still covers higher rents, but perhaps doesn't help enough in terms of buying depending on where in London you are looking. So whilst I think the higher salary doesn't "justify" the increased costs, I think it almost/pretty much compensates.
Anyway, I am in two minds about relocation! I like the idea of moving to Yorkshire and buying a big house but think that a lot of other costs would be higher (for example we don't own a car and to buy one or two of those and insure, put petrol in etc seems expensive!). Plus I think I would miss having so much to do all the time on my doorstep.
lol
east end of glasgow. would love a garden but we can't afford to move at the moment and i would hate to not be so close to the city centre! 
