Gunna have my say now.....i don't think this is in anyway unreasonable. Your working on an old system, with issues and peotential problems that may and often do arise. Once a quote is given risk passes to the engineer....ie fixed price. So if he spends 2 hours trying to unairlock a system say he still gets paid the same. Customers need to realise that yes, 80% of the time a fair price offered is a fair price paid, sometimes you as an engineer have to build a cushion into a price, as has been stated, the 'work' may consist of 2 hours, the travel there and back may add another 1.5, and what about issues? Maybe it goes sweet, sometimes it doesn't. I don't bitch if i struggle to get an old joint to seal and it takes me longer.......the alternative is to quote hrly rate, but then the risk passes back to consumer and this one seems to want his cake and eat it....fixed price but it's too much.....ok, pay by the hour. It maybe a tad high, but i wouldn't crucify, we ain't seen the job. The amount of times i have kicked myself in the past for saying, oh thats x on the phone.....to find, no access, old imperial pipes, sludged systems....etc etc...So, now i learned my leasson and add a little cushion to jobs It's up to the customer to accept or not. I am not condoning ripping people off but take changing an imersion.....some i drain, disconnect the electrics, hard push with spanner and replace....20 mins. Others, old wiring literally falls to peices, the bright spark who fitted the cylinder has faced the immersion to the back, it won't come out, i sweat and curse, i drill it, i replace, it weeps, i drain i rewrap, i fill, it locks up, i replace wiring, old junction box splits i replace nearly 2 hrs...1 price....you get my meaning......