Framing the superstructure of a building is always the fastest part. Site preparation beforehand and installing services and finishes afterwards are what takes most of the time.

Keep in mind that 200 hours is the time on site. It doesn't include lead time. If there are ten projects ahead of yours, you're 2000 hours out and because there is a dependency on a particular machine, you just have to wait. While you are waiting for your 200 hours, there will be weather delays on the other projects. Other owners will be like you and decide to add an extra room while the machine is there. Framing crews are largely fungible. Proprietary machines and materials are not.

So now it is finally your turn. Any other trades that need to be onsite haven't been sitting around waiting. They are off on other projects with their own schedules, delays, change orders and problems. Sure you scheduled them for 2200 hours out, but that turned out to be 3200 hours and the plumber will be free at the 3700 hour mark and the electrician at t=4000 hours. Because that's the way construction actually works.

It's why everyone has heard horror stories. It's why 200 hours sounds too good to be true. I mean how long will it take you to find a piece of land with suitable soil? How much time will it take to figure out where to put your strip mine on the property?

Also keep in mind that 200 hours is five forty hour work weeks (and 2000 hours a work year). That 3d printer has to be fed by someone and that someone won’t be working round the clock.