BobG, it sounds like you worked for the same guy one of my friends had build a house for him (one he broke the contract on because the builder was insisting it was done and pushing to get the C.O. while there was still a small lake in the basement...there were a few other shady things and short-cuts caught along the way that my friend decided it was worth the effort of breaking the contract, even if it had to go to court). I think that whole house was built twice, first the way the contractors built it, and then when my friend found what they did wrong each day, they tore down the day's work and did it over again the right way.
I've run into those problems repeatedly of someone ordering the wrong parts for things. Drives me nuts! Oh, and then there was the 6 month delay in opening our new lab animal facility at work (on top of the year delay, which was of course expected for construction at a university). Some dingbat connected ALL the plumbing, including the high pressure cage washers, to the residential water supply instead of the industrial supply (I think that was the distinction...I'm not an engineer...but it had to do with connecting to a lower pressure supply compared with a higher pressure or larger flow supply, or something like that), so every time they tested the cage wash, the water pressure in the rest of the facility dropped to virtually nothing. Most of the delay in fixing it was deciding who would pay to fix it since the project was already delayed and over-budget. Every sink leaked, every door is hung crooked (I'm still waiting on them to get the right type of weather-stripping to finish light-proofing the door for our dark room, 9 months after the facility opened), some nitwit made the executive decision that the rooms shouldn't have floor drains, so the people who work there have to spend ridiculous amounts of time mopping up the water after washing down the rooms rather than just letting it run to a floor drain, and the main entrance won't stay locked because the electric eye that detects someone approaching unlocks it every time someone walks in the hallway. This is the same building where we have two elevator shafts, but only one elevator because they ran over budget and couldn't afford the second elevator, and apparently they could only afford the slowest elevator imaginable (it does inspire us to take stairs...on most days, I can walk the stairs faster than the elevator...it's always fun to wave to someone waiting for the elevator as I head to the stairs, and then greet them at the top when the elevator finally arrives).
Oh, just give me enough time, I could come up with lots of stories of incompetent people!