addition timelines
 

I am adding a utility room to my house now. The next addition I want is a master bedroom/bath/ WIC. Would I waste a lot of money if I do the bedroom now then come back later with the bath and WIC? The house is paid for and I am wanting just to pay for each project as I go.

It will most likely cost more overall to do it that way.
Everybody(excavator, foundation formers, carpenters, drywallers, roofers, electricians, etc.) will have to come back twice.

The money you don't spend now can be invested or used elsewhere. Depending on the costs & benefits & risks of each choice it might make sense to wait.

I guess a related concept is 'opportunity cost.'

I would plan on doing all the rough work at one time. Foundation work, framing, roof, siding, plumbing, heating, wiring and insulation. Now you can do the rest whenever you want.