Why can’t the 20 homes be built in the same affluent areas though?
Why do those who have to rely on social housing have to live in the ‘less desirable’ areas?’ Is that not social segregation?
Where would you put them? We’re talking heavily built-up central London, where there is no brownfield available; are you seriously advocating demolishing a perfectly good, expensive house just to build a small block of cheap, shoddily built apartments?
The only possible places to put the new housing is on regenerated industrial land, like the Olympic park; the costs of reclaiming often heavily polluted industrial sites are massive, so selling high-value buildings in places where the prospective buyers are likely able to afford them in order to fund the clean-up and building of new developments where there is the space for them makes perfect sense.
Or else take large empty office blocks and convert them to low-rent apartments for lower-paid local workers, which makes sense, and, as has been mentioned, force landlords to open up empty accommodation above shops.
Even in my small-ish market town, there are quite a few shops in the high street with clearly under utilised upper floors that could be used for housing people, despite the oft-cited ‘security issues’!
And as for ‘less desirable areas’, well, there’s no reason those areas should be less desirable; I’m sure many people would prefer to live away from a noisy, cluttered city centre where there’s nowhere for the kids to play.
I’ve stayed over in a flat in the centre of Bath, when it was necessary to have the window open at night, and the noise from rowdy drunks at 3am after they’ve left the clubs was soul destroying! It’s the last place I’d want to live, right in a city centre.