The builders should have issued you with an 'Electrical Installations Completition Certificate", from which you will get you MPRM number which the ESB need to fit your meter.
We bought a house and this was the case, although I'm not entirely sure with regards an apartment block.
However, the fact you're already in, would suggest the meter has already been fitted. Our place is also still a building site, best to ask the foreman i suppose