> DIY makes sense if you either 1) enjoy it or 2) are in a position to need to spend your time to save money (and carefully evaluate tradeoffs about when it would cost you more money to DIY because a professional will have everything they need and you don't and won't need it again).

First hand experience. I have a 2 story house. I was going crazy with people walking upstairs while I was trying to work in my office downstairs. Got hold of a flooring guy who has hundreds of glowing positive reviews, and offered multiple references. He wanted to rip out the carpet and screw the floorboard to the joists, more. Got his work contract and added the clause that he will not get paid unless the sounds stay gone for 3 months after the job. Paid a premium for the clause. The creaking came back in 2 months and the impact noise never went away.

Got hold of another guy and he said, sorry can't do anything about the noise beyond what is already done. The third one said the same as well.

Finally got frustrated enough to do my own research and came up with materials and techniques that I had to "import" from California to Washington. Bought a bunch of tools. Now I have no noise, and as a bonus, ran conduit in the floor to have OS2 fiber everywhere in the house.

DIY is not always about saving money. It is also about getting the job done so it stays done and not doing the bare minimum to make it legal and to get paid.