I agree that there are many great landlords who take great care of their properties - I've been fortunate enough to live in some of those properties. At the same time, we know for a fact that many rental houses are damp and cold, and injurious to health, and it's not ok. Damage by tenants is really awful, but we do have the courts to deal with that issue. What we lack is courts that can deal effectively with issues of quality, and what we need, as you say, is something like a WOF, which regulates for quality.