1. No need to diagnose...it's the PRV.
2. Simple fix to cut that valve out & replace with ball valve as shown above.
3. I'm a fan of the Watts U5B. It's a high flow higher quality valve. About $200
4. Easy fix. Do you have the spout?
5. "T" off near WH & install TET. $75
6. Hammer arresters need to be installed at each appliance. ie. at ice maker connection. At washing machine hookup connection, etc. I'd wait till everything else is fixed & see where they may be needed.
Plus labor...which will be all over the board.
1. Positive? Even though I have replaced it twice in less than 6 months? The one that was in the house before lasted 15 years and it was a Watts N35B which is in a similar price range of the 2 Cash Acme PRVs I replaced it with (EB-45 & EB45DU). I would hate to spend 200.00 on a new valve and have that not be the problem.
2. I know it would be simple for a plumber. I'm just looking for how $imple it might be when I get the bill.
3. See #1
4. Yes, I have the spout. Again, what would a plumber charge for 1 solder connection?
5. I think I may be able to do this myself but depending upon what a plumber would charge, I might have them do it as part of a package job. If I did it myself, I would probably use a Sharkbite T (shhhhh.... don't tell anyone) along with a stainless or copper flex hose to mount it on the wall behind the tank. I don't really have room to mount it horizontal and inline with the pipe.
6. Yea, I bet when I finally figure out the where the noise is coming from, I won't really need the hammer arresters. I've never had them before other than one about 10 inches tall that was mounted on the cold water side of the old hot water tank that I replaced about 18 months ago.
Now.... any thoughts on labor? Are we talking 100? 200? 500? 1000? Just trying to get a gauge as I have never hired a plumber before other than to unclog a drain 20 years ago. I guess I just need to call a couple and go from there.