Greetings for start, it was real challenge and real pleasure at the same time to participate in this contest, hope You will find your best solution will be able to enjoy in your inspirative home... I worked briefly on this problem of space, function and light, trying to put service space in the middle, also near the potential installations (always one above another so to cut expenses on installation works)... Putting the bathroom, kitchen, hall and some storage parts in the middle i opened the space for living and sleeping rooms, as those were the main request from you. I think there were no enough space for all demands but i gave my best without going into the complicated systems...
Main connection for all tenants are those stairs in the middle, also the passage to the garden, so it was "must to" destroy that part of existing building. Some playing with levels in house are also very limited, cause one can not use part of the main stairs as private space (as it was, for closet in the existing plan)... so every change of level required new stairs and i tried to avoid those schemes... think it was not worth it...
At final, 4 big apartments came of out of the volume, very similar on plans, working like modules, so you can enter everyone through stairs... back facade is dynamic, very uneven from all those regulations and borders, so i tried to give it lively appearance, with big openings and slopes that invites light to come in.. some wooden brise soleils could be combined with those wooden frames of windows, so to give protection from summer sun and allow winter heat to come deep into the volume...
I hope you find some interesting themes by this work, wish you all best and let the best win