Some people have no pride in their trade, the skills required or the responsibilities they take on.
A smart consumer wouldn't dream of letting you in the door for £20.00, consider this, in 1978 I worked for a company servicing oil boilers, the minimum charge which had to be collected before I went near the boiler was £15.00.
A brand new Ford Escort van was around £1,500.00 at the time, it cost £6.00 to fill from the red line so lets use Henry Ford as our guide to inflation, How much is a new Transit Connect today?
Roughly £15,000 so either lose your customers or charge realistic prices because if you don't you will end up grumpy old men wondering why you have nothing except social welfare when your due to retire.
If you don't have respect for yourselves how can any of you expect a consumer to respect the services you have to offer?