The joys of renting. We signed one tenancy agreement only because it was so shoddy that the vast majority of it wouldn't be legally enforceable (Black Katz I seem to remember).
We also had one landlord who put the flat on the market about two weeks after we moved in. Anyone who came to view the flat was told that we wouldn't trust the landlord at all and they should be very wary of doing something like buying a flat from them. It was still on the market when we moved out.