Warning for both landlords and tenants!
I am a professional who owns two properties and have two tenants myself and due to work situation rented a house through the agency a year ago. I found out in the last year that they can not be good for neighther the tenants nor the landlord. The rationale is that they are not bothered to look for reasonable services around and use very immoral and expensive contractors (in other words Cow Boys) who charge enormously and sometimes unnecessarily for the most little things in the house. This causes a lot of expenses for the landlords to keep their houses with them. Moreover it causes extraordinary expenses for the tenants at the time of moving out of the property! for instance they might charge you for fixing a nail on the courtain rail for £100!! They also impose a lot of unnecssary admin charges which can not be justified! In terms of their comunication when they need something from you, they are very quick however when you need them, there is little response!
I have decided that I will not deal with them again in the future and will recommend you the same.