Rohbau in order or defective? Experiences?

I mean that the master mason sits down with the architect’s plan and just looks at where to place which stones and how, so that cutting is minimized and the overlap dimensions are adhered to. There are even programs for that, with which you could then also order from the stone supplier. Most people just save themselves that.

I only know something like that from prefabricated houses or from their suppliers for their customers (contractors), who also want to "calculate" individual designs as a virtual prefabricated house for costing purposes. A trained mason does not need something like that in practice, and a good (shell construction) general contractor has a foreman or a master-skilled experienced journeyman in every crew.

And of course you almost always have to cut at openings, precisely because of the overlap and because hardly any shell builder actually orders half bricks.

The professionals use both special jamb stones and, with proper planning, the stones only need to be cut in such a way that the "rest" can be used elsewhere as a B-piece. Waste as scrap fundamentally arises from dimension-ignorant planning.

Does anyone know of tricks in general to find a really good company for shell construction? I don’t want to save money here, but rather focus on quality.

I do this professionally and have to deal with reality, as my job cannot be done by a "trick." However, one approach to a trick was already mentioned: you could recognize such companies by whether they use jamb stones – because those only make sense if you work with trained masons. Temporary intern actors wouldn’t know anything meaningful to do with that. On construction sites alone, you can’t easily tell whether a lot of cutting is due to poor workers or poor planners. Roughly, you can say, the worse the planner is, the more often cutting produces waste pieces instead of B-pieces.