I'd be happy to maintain an aircraft that I fly in....there is a good incentive to do it properly. I would of course ask for a competent aircraft engineer to carry out certain tasks, but because he wouldn't need a calibrated spirit level, then his costs wouldn't be so high....
Yes really, a CAA inspector asked our maintenance org for their calibration certificate of the spirit level in the cupboard. No wonder they have to charge what they do, much of their time is spent fighting off stupid audits.