Hi,
The water pipe in the wall is common property, but the taps are in fact the Lot owners. You can now buy taps that have in built tempering, so go to Reece or some other plumbing supplies and look at what is available. You will have a separate master water shutoff to your unit so it should take all of a few minutes to fix your issue, without any permission needed from the OC.
If you are not a handy person call a local plumber to help with advice and install.
Chris Mo’ane