Somewhat related to the topic, but not a direct response to the original question.
We built an apartment complex last year. Come final trim, we started having a real problem with water hammer when the tub/shower valves were in use. We disassembled the valves, looked for debris, looked for torn/loose washers, not just one of us once but several of us several times. The problem persisted. It took a bit of convincing, but I finally got our project foreman to allow me to install water hammer arrestors on the adjacent lavatory supply piping. The problem went away. The manufacturer of the valves came out, said that some springs needed changing, and paid us to change them. The problem persisted. They had us change more stuff, and so on. The last I heard, they had paid us to put hammer arrestors under the lavatorys.........
We installed the code required hammer arrestors on the icemakers, dishwashers, and both sides of the washing machine box. These were not enough to "arrest" the problem.