Well, I tried to shut off the gate valves under the sink so that I could install new washers on the kitchen faucets and found two problems.
The hot water valve closed and immediately started leaking. Since it's a high-rise condominium, I don't have immediate access to the watershutoff. I tightened the compression nut as tight as I could and that stopped the leaking --- but every time I reopen the hot water valve, it leaks.
The cold water valve won't budge!!! I'm pretty big with years of weight lifting behind me but it won't move at all.
Appreciate any help from the plumbing experts out there.
DJ