Fitting a towel rail?

My daughter has had a rad removed by her other half [long story as he's not with her now] and wants to have fitted to the existing central heating rad pipes a towel rail curved about 4ft 6ins high. Easy clear access to pipes.
Question: How many crisp £20 notes should she pay for this. She is in North Devon so shouldn't be London prices. I don't want her to be stitched up.
My estimate would be max £60 for around hours work, may be less.
Many thanks

Bob
November 2010