There's a lot more to it. The scheme is in place, and yes, it is available to single people as long as the property is fit for purpose, eg a single person in a 4-bed house would not qualify. Summary of the scheme is [broken link removed].
While the costs may well increase, the scheme is limited in the number who can partake of it. Also the housing agency purchasing the property is buying at current market value, at the bottom of the market, and as they are long term purchases, the socail housing agencies will be asset rich in the future.