My advice to all prospective tenants is to stay away from this agency at all costs, even if they are the sole agent for a property.
I made the mistake of putting an offer through them and giving them a holding deposit for that property. For 2 weeks they were messing me about that the landlord had accepted in writing my offer and we had even agreed the move in date and the changes in the furniture in the flat. I kept pushing to sign the contract and they were holding back with various excuses.
In the end they admitted that the landlord had never accepted my offer. A week before my supposed move in date I was found homeless due to their fault and instead of apologising they even messed me about with the holding deposit. Three weeks later and despite my numerous phonecalls and emails I still haven't got back my holding deposit. They don't even return my calls.
I don't think I have encountered a worse property service elsewhere and I have rented a lot of properties in my life.