My widowed Dad lives in a council flat and he gets reduced rent etc. I have offered to buy his flat for him, but he says because he is on these benefits, I won't be allowed to buy it and he will have to pay back all the benefits that he has received. Is he right? Or the council will let me buy his flat for him, despite the fact he is on benefits and has no savings.
You cannot buy the flat, he can with a discount. If you choose to fund him in this that's your choice. He will loose the "benefit" of reduced rent but not other benefits. He will not have to repay benefits in this situation. Benefits only have to be repaid if they have been falsely claimed.
Is the flat in a large block? If so, before going ahead find out what the position will be about service charges once he has bought the flat. Many people who have bought their council flats have later been horrified to be presented with bills of many thousands of pounds for major maintenance and upgrading to the block. This can be a real downside to buying council flats, as opposed to council houses where the problem does not normally arise.