There's to Much kit out there for them to be able to effectively enforce there regs , so everyone doing pretty much what they want these days , unless someone knows who to complain to, no one cares man , ico don't know Jack what's going on in the grand scheme of things....imo
I think op wants diy fix, system is locked or doesn't know how to default or programme , most of above doesn't make sense (not trade comments), owner would upgrade if paid for , company would install if paid for, and tenant wants to put there own system in? If that's the case, how is other system affecting them?