That again speaks for the fact that your general contractor is not only a pleasant partner himself, but also only does business with such partners. You can only afford such "vague" formulations if there is agreement in the basic conviction: that contracts are agreements between business partners, and not demarcation lines for disputants.
That’s really the case. In rural areas, the clocks tick a little differently. The entire construction service description is relatively vague in that respect – for example, it states "sanitary fixtures standard version, standard color white." That can mean anything and nothing. At first I was a bit afraid of the construction because we had previously built with T&M and with them everything is very precisely regulated – which is basically not a bad thing. So far we are satisfied with both construction companies; it’s just completely DIFFERENT. With T&M, every change order was signed by us, every additional cost was clarified down to the cent. But for our shampoo niche in the bathroom, there was also about 500€ on the invoice. Keeping all these things in mind, I discussed this with the new construction company as well, that we want shampoo niches in the bathroom. His statement was, "if you want it like that, then we’ll build it like that." And in his case, the effort is significantly greater because he has to rebuild an entire wall (the wall between the bathroom and utility room would otherwise be a little too thin to take anything out there). At the same time, I have in the construction service description a lift-and-slide system over 5 meters, which is only there by mistake (copy-paste error). As a disputant, I could insist on that now ("But that’s what’s in the contract!"), but we would never even think of that. We pay an extra charge for our lift-and-slide system because we did not plan and discuss it in advance. You meet each other halfway instead of getting in each other’s way. It’s a very pleasant way to build.
Color selectable can also mean everything costs extra. The pendulum can swing both ways. Mine was something similar in our Heinz von Heiden offer back then, where only white would have been free.
I can hardly imagine that in our case. We have a position in the contract that is subject to extra charge; it says so. So something like "Air conditioning for an extra charge." .