Hi Ishaw18,
Welcome to the forum.
If you do a search through the threads (top row with the black background - 3rd from the right) you'll find this has been discussed before
It depends on the type of service you require since agents can do everything or just check the form.
It also depends on where your agent is and where you are because of exchange rates. We used an agent in the UK but it might have been cheaper to use one in Australia.
Regards,
Karen