You see, all this is part of the reason I've been self employed for the last 25 years. I decide on my hourly rate, get it wrong and I don't get work. Funny thing is that doesn't neccesarily mean too high, you can be too low - then people think you're no good.
Main thing are, I keep below the vat threshold, don't have any dead weight office staff to support and am van based, so no bussiness rates etc. Also I don't advertise (bussiness cards only) as I get my work by reccomendation.
Maybe someone could set up a van based cycle workshop, tout themselves to all lbs's in the area and advertise to the public too. That way they can set their own rate and if someone treats them badly, they can walk away.