This may be a stupid question, but how does hot water work in blocks of flats/apartments?
Do you have a communal heated system or do you each have a small boiler or is it electric heated?
Normally either or, some have fully electric heating and hot water using a tank and immersion heaters. Others have a central boiler system and zone valves to supply heat to each flat.
Never a gas supply to the flats for cookers etc.