Can I do my own plumbing if I do it according to the codes and I am not in a union? Also why do I have to pay for a plumber that is qualified in drainlaying, gasfitting and roofing when all I need is to fix a small leak in my faucet? It's like when you need to reinstall Windows on your PC you cannot do it yourself and have to get a software engineer for $500/hr who can write assembly code and knows the difference between merge and quicksort.