Granted the pressure is high if it can briefly get to 100. However,
given that the water heater in my townhouse has lasted 21 years
without a leak, would it be unreasonable for me to believe that the
water pressure really isn't a problem? My mom lives in the same
development and she does not have a PRV valve either. I only know of
one neighbor that has one.

Nobody is requiring that I install a PRV valve. It is a question of
whether or not it is a good idea to install or a waste of money.

You seem to be trying to rationalize your decision not to spend the
extra money to put in a PRV and tank. *Whether it's 115 or 100 it's
still high. *You seem to think that a leak will occur at an averagepressurereading. *That is not how it works. *Or maybe you're hoping
that a low reading will convince the leak not to happen at all?

You are asking questions that people in your location are best able to
answer. *Our water district has some odd requirements and it is
pointless to argue with them. *Why not pick up the phone and call
another plumber? *If you don't have one you trust, ask neighbors and
friends for some names.

R