Seeing as how they are mechanics they generally get the same rate as automotive mechanics do.
Around here that averages something in the $75-$80 range, naturally there is always the back yard guy that charges less and usually for cash.
In some areas there is the freelance mobile guy with the well equipped truck but then his rates will compare to the dealer rate. Downside he will not have model specific parts on hand but generally have hoses and fittings and some generic items. He should have compressed air and some welding capabilities.
Those freelance types are usually only found by word of mouth as they do not advertise.
