But for that the density reachable without elevators (if you're ignoring accessibility; i.e., 4~6 floors plus basement) suffices. And yeah, having the bottom f

But for that the density reachable without elevators (if you're ignoring accessibility; i.e., 4~6 floors plus basement) suffices. And yeah, having the bottom floor be commercial is often effective. Even if it's just a GP's doctor's office. Look at pre-WW1 urban core neighborhoods in Germany, for example.