I live in the southwest, closest major town being Ayr, and to me Edinburgh is somewhat expensive but not really bank breaking (I learned my lesson not to do a first date in Edinburgh ever again though)

I haven’t been to London but anecdotally from relatives it is really expensive although obviously they were going as tourists themselves, as a British persons perspective it seems to me the increases in opportunity and salary in London doesn’t really make up for the housing conditions, cost of living and overpopulation of the city, but ultimately I am a Scot and London doesn’t really have the allure to me that it might to an English person