Have used several Agents over the past 8 years
Most have been reasonable but one has been a total waste of time
It appears that the larger Estate agent companies operate in a semi professional manner. However some of the smaller outfits are operating like scam artists. They are only concerned with getting money from the Owners and the Tenant.
Prospective tenants should be careful when dealing with Agents. Make sure you get everything in writing. Even then you might be in for some surprises.