We found a flat and had to use this agency to take care of the paperwork, viewing etc. Initially they were nice and very knowledgeable about the property. Too bad they didn't disclose everything on a timely basis.
We had spoken to them numerous times after we had our offer accepted, we paid out deposits and ordered movers, packed up our things. When we were at the office just about to sign the agreement, they tell us "by the way, the flat is also listed for SALE". So based on the lease we had agreed on, we could be kicked out after 6mths if it were sold. And we would have viewings constantly in our newly found flat. She had us by the balls, we couldn't do anything except grin and sign the bloody lease.
Now there is an offer on the flat and we are at risk of getting kicked and having to find somewhere else to live. Beware of them, make sure you ask them all the Qs and then go back and ask someone else.