It is somewhat unclear what part of the electrical design for this building you are expected to provide. In the US, you could not perform this task, as it must be accomplished by a licensed Professional Engineer if it is a commercial Architectural construction project, or by a registered Electrician if a Design-build in a municipality that requires that kind of code compliance, either of which would mean that you could not have design responsibility if you do not already know what you are doing.

If you are simply to provide advice to the design or oversight for the project, as your employers representive for instance, than any residential Do-It-Yourself manual will help you get the basics of what you should expect to see on the design and on the project.

One of the best inexpensive manuals for simple residential circuits is put out here in the US by Black & Decker, with obvious color photos of all typical situations and some discussion of issues that are code-compliance items here in the US. It's available on amazon.com/Complete-Guide-Home-Wiring-Information/dp/1589232135

This includes things like all panel circuit-breakers serving bedroom outlets must now be Arc-Fault Circuit Interupter type, and all outlets serving kitchen counters must be Ground-Fault Circuit interupting, either at the receptacle or at the breaker (your choice). It also has some good lighting design advice.

As for simple advice on how to 'set it up,' I would recommend the economy and ability to meter usage at each apartment, of running a 100A "Service Entry Cable" from a central meter stack location (or from a Main Distribution Panel if no sub-metering required) with a main breaker for each apartment there, and use a small 100A main-lug-only panel in each apartment.

Also recommend using a tankless water heater in each apartment.That way there's no big tank to keep hot at every flat so energy is saved, no extra floordrain required in the closet of every flat, and nobody ever runs out of hot water. Costs a bit more to install, but saves a LOT of money over the life of the building, whether they are gas-burning or electric two-stage type.

I'd require every center-of-the-room ceiling light outlet be a FAN-rated type back-box, so a ceiling fan could be installed at any suitable location without worry in the future.

Be sure to tie the smoke alarms together within each unit.

Go to mikeholt.com if you have any "how does the safe US electrical code handle this" questions.