Trouble is,rightly or wrongly, the goverment policy has been to make it less and less appealing for private landlords to be in the market who then sell there properties as its not worth the hassle.
This then leads to a shortage so rents climb, also a lot of private landlords will be on buy to let mortgages and with the increase will have to pass this on to the tenant.
Not sure what the answer is ,in Stockport they seem to be building flats everywhere but unless social housing take some or private landords buy them they will get sold to private owners
Whilst this is a good thing it doesnt help the rental sector which there will always be a need for .