Renovating one apartment at a time, utilities challenge

[Paul M.]

For financial and available time reasons, I might need to renovate one apartment at time, in a building where the apartments are stacked on top of each other. These would be gut renovations. How feasible is this with the utilities, esp the plumbing?

Plumbing I imagine 3 units on top of each other share one plumbing stack, so it seems like it would be difficult to replace that, but maybe one section at a time can be replaced? Also would have to run water supply lines and electrical, but maybe I can find a chase for those. Ductwork also likely a challenge.

Is this just unrealistic? People do it all the time, right, but are they not running new utilities?