Everything Mum2Ramone said.

Also ring your local Tenants Advocacy Service, They will give you free advice and even free representation at tribunnal if you need it, and I personally would be taking this to tribunnal - they would give him a swift kick up the rear quick smart. It is LL like your who give everyone else a bad name:If they are going to get into property investment, then they should learn the rules of the game, a LL has responsibilities to their tenant.