I don't think its a good idea to use an out of area agent, Clarkson and Dianella... worlds apart, and there lies the risk. The RE agent needs to know the area back to front and may also have a data base of potential buyers.
We have an out of area agent selling on my street at the moment, has no clue what he is doing, costing the seller valuable time as he has the property overpriced and it will sit and sit and they will eventually shoot themselves in the foot.