I gave them 1 star because there is no lower rating. Firstly, our property was not ready to be moved in to (damage inside and outside the property, some appliances left in lethal condition e.g. lawnmower tied together with duct tape that came apart during use), about 20 things were badly wrong. It is 3 months into our tenancy and they still have not fixed the issues. Keys missing for rooms/external doors, big drainage hole on the patio, a broken bed and wiring sticking out of walls were just a few issues worthy of note.
Dealing with the Maintenance Department is a nightmare. They never return calls (just yesterday I called them, and was told after a quick call to contractors they would get back to me; they have not) even if you leave a message with a person. They are incompetent (our contact said he would have a meeting with his manager which, it later transpired, never took place) and upon complaining they have treated us to apologies and excuses and claims that it is an "isolated incident". I see from reviews on this website that it is not, as others seem to be having some of the same problems. Once they get your money, they do not care at all; the local branch manager told us she was washing her hands of us because we had signed the contract and couldn't speak to anyone face to face.
Something others may also find interesting is that we have been told that it is not their company policy to actually check properties before tenants move in; you could get a property in any condition, you will not know with them. Our landlady has had massive problems with them and will not be using them again.
What agent could do to change your mind?
Just do what an estate agent should. Stop being such a useless service, do what you are paid to do.