Avoid at all cost. We visited two flats and made offers. First time, they told us that the landlord received a better offer from another agency. Our offer was finally rejected. Fair enough, however, we had to struggle for days in order for them to let us know. We visited another flat with them and made another offer. This time, they told us that the offer was accepted and we kept asking for a written confirmation which never came. One week after they told us that the landlord might have changed his mind and considers selling the flat (as in many other reviews). After more than a week and paying 500, we still don't know if we'll get anything. Basically, we email/ring/go there every day in order to ask our money or a contract.
Once we made our offer, it was very difficult to get in touch with them and they really did not care letting us wait for days and days without knowing anything about the situation.
On top of that, the first flat that was '