It's not as simplistic as that. If I want a mansion or grand large estate they are for sale. Want a modest sized apartment or average size family home almost nothing for sale in some areas.
"...In its report, Daft noted that the total number of properties available to buy on its website – as of June 21st – was fewer than 12,500, up slightly from the March total (11,900), but down by more than 6,000 on the same period last year..."
When it comes to supply of so called "affordable" housing by the govt"
"...Just 400 affordable homes will be delivered next year under a government scheme launched three years ago that is supposed to deliver 6,200 homes to buy or rent...."