Sorry for the delay but I've got the answer, straight from the horse's mouth�
Regarding the agent, it would be standard practice for any agent to charge for selling a house. Their principal role is one of introduction and they have done exactly what any other agent would have done - marketed the house and found a buyer.
1.5% is a fairly good rate - some London agents would charge as much as 3%. If your friend had instructed an estate agent to sell the property they would likely have paid at least this, if not more. Having said that, I suspect they would be happy to negotiate the percentage on the basis that it has hardly taken up a lot of their time!! My experience is that most agents are reasonable and if they have not been involved in the price negotiations for the purchase, or overseeing the progress of the sale then part of their job has been done for them.
Two things to do:
1. Carefully check the agency terms. They must clearly state all fees in the terms of business. If they have not been clear about the sale fee, then contest it.
2. Investigate what the typical sales percentage in the area is by calling 3 or 4 sales specialists. I would assume it to be between 1.5% and 2%+VAT. If so, offer the the letting agent 0.75% of the purchase price and I suspect they will either agree or settle at 1% rather than sour relations. Top tip: when speaking to the agent, approach someone you know in a friendly manner and explain the deal simply. If they are approached with aggression they will dig their heals in.
Hope that helps!