There are multiple stages or degrees of "living alone", and it's very difficult to satisfy all of them without a number of physical moves that you can't buy space very far in advance.

a) shared room with parents b) shared room with siblings c) separate space/room, shared meal preparation and amenities d) separate house/apartment, walking distance for many shared meals and events e) separate household, rare visits f) separate household, moving through it's own phases a-e.

It's hard to know when each of these phases will become appropriate to an individual, nor the individual preferences for variation in distance and specifics of house. Also, building a house is harder than you think.