Hi all, I have a few questions on a water pressure regulator. Had a plumber installing a new sink & garbage disposal for the home builder on a 10 year old house. The kitchen sink comes on with so-so pressure for a few moments and then the pressure starts to taper down. The pressure in the front bathroom pressure seems OK so I've always thought low pressure in the kitchen was because of the location of the kitchen in the back of the house,-furthest down the line in the house. Any way the plumber goes outside to the regulator and says that the diaphragm inside sounds like it is going bad on the incoming 1 inch water supply line. He went out and put a water gauge on it & said it was fluctuating. He said it would cost 400 bucks to change the pressure regulator. The plumber said since we have pex pluming system we really can't afford for the regulator to fail & bring in city water pressure of over 120 psi. It looks like we have a 1 inch supply line coming in to our house and the previous owner painted the entire regulator so I can't see who makes it or anything else. So, I live in southern California and I wonder if this is a good price to do that job. I saw some 1 inch water supply pressure regulators at Home Depot & the ranged from 80 to 150 bucks!!(not that I would know which is the correct regulator to get). Can these regulators be rebuilt in place? Or are they hard to change out? Ours look like it has 2 nuts on it (one on each end). Any ideas ??