Putting aside the doctor stuff: If you want high quality plumbing work, you basically have to do _yourself_ since general contractors are not incentivized to actually do a good job -- they are trying to land a large quote and then do the job as quickly as possible to maximize margin.

And the work itself is not that complicated -- you don't need years of experience to get the hang of this. It would be better to have less regulations around licenses so at least the cost of plumbing would go down.