I trust only two mechanics with my bike(s).Myself and a mate who works for Halfords.To be fair to him he has been a fully trained cycle mechanic for the best part of 28 years and only works at Halfords as it suits his childcare needs and his wife is the main earner.He's just moved shops and he says there's a common factor in the four Halfords he's worked.All the 'mechanics' are youngsters(under 25) and none are actually certified other than by Halfords.Generally if a mechanic is off they use an employee from another area to fill in and do 'easy' jobs
How much would I want if I were to 'rebuild/check' a bike previously built by Halfords or online?Tricky one as it doesn't actually take long to strip/grease/rebuild/refit etc and would someone who only wants to pay £100-£300 really want to pay another £40-£50 to have it checked?
If I were to do it for a friend etc then I'd charge a couple of beers.If it were my job however then it actually boils down to time/travel time etc.
£50 IMO is not unreasonable for a Mobile-cycle mechanic for their time and experience.Any parts would need to be extra.
One of our CC members started a Mobile Cycle mechanic business(pre Covid) and he struggled and eventually gave in.It's an odd one.Those who ride seriously tend to do their own spanner work and those who buy bikes for kids/holidays/occasional use just won't pay the sort of fees involved.
He now walks dogs for a living!