I'm installing a new basin/mixer in my downstairs cloakroom (where the old
basin had two separate taps).
Now as the cold is fed by the rising main, and the hot by the tank in the
loft I have a pressure imbalance to cope with.
I believe this requires a pressure reducer valve on the cold feed.
I also require each feed to have a single check valve to prevent cross flow
between hot water and rising main.
Then I also wanted to add a service valve to each feed so I can turn off the
water to the basin.

The pipes come through the wall from the kitchen behind kitchen cabinets,
and I don't have a lot of room to install all this stuff below the basin.
Unfortunately the mixer tap doesn't have built in service valves.
Are there any clever fittings that combine say the single check valve with a
service valve, or a pressure reducer with a check valve and service valve ?
Tony