Total cost for a 190 sqm house (flat plot, without basement)

I would always do a preliminary sampling if possible. After that, you’ll be a bit wiser. I would never spend 12,000 or more on a kitchen. My pain threshold would be 7,000 including appliances. We currently have a used one from Sconto; including appliances, we paid about 1,600€. I have roughly planned a new kitchen at Ikea for 5,000€. But admittedly, I’m not very demanding. Average appliances are enough for me; and Ikea meets my requirements perfectly.

Ours was at 18,000. Well, our stove and the suit for it already cost as much as some kitchens... It always depends on what you value.

Construction site toilet, protective scaffolding are included. Probably not the waste. We recycle the excavated soil.
Regarding the gutter it says "Vertical rainwater downpipes in the ground made of PVC. Connection to the house drainage under the slab in a combined system. The pipes end at the outer edge of the building body towards the inspection shaft."

Is this usual, or is more needed? "Base plaster around the slab on 100mm thermal insulation, height approx. 30cm. Additional areas will be charged based on effort."

@Kitchen: I see it similarly to - we will take a few appliances with us, we are not into design but into functionality :)

Well, it doesn't have to be the brand name that's paid for. Sure, then you're looking at 40k euros and up, which in my opinion no one needs. But 12k euros is very tight for a kitchen in a single-family house, no matter the brand. A good guideline is 20k euros, it can be slightly less or slightly more. But it usually settles around that.

20k is overly ambitious; that's no longer standard. For that, you have to go for very expensive fronts/handles, appliances, and countertops in the mid-range. Our kitchen (Leicht, just under 8 linear meters, compact countertop, induction, Berbel, etc.) cost us 17k.

Regarding the gutter, it says, "Vertical rainwater downpipes in the ground made of PVC. Connection to the house drainage under the slab in the combined system. The pipes end at the outer edge of the building structure towards the inspection chamber."

Then the part that leads from the outer edge of the building structure to the inspection chamber would be missing. But that probably isn't all that much anymore.
Connection for gas/water/electricity/telephone is missing, for example, or is that included in your additional costs?

20k for a kitchen?? no -
Rounded up 10 for the furniture including sink and lighting, and less than 5 for the appliances. Miele.
And that certainly could have been cheaper, but we wanted a kitchen from the region, and repainted fronts, and with Häcker you end up roughly in that range.

Then the part that leads from the outer edge of the building structure to the inspection shaft would be missing. However, that should not be too much.
Connection for gas/water/electricity/telephone is missing, for example, or is that included in your additional costs?

Exactly, water/electricity/telephone are included in the additional costs.
Thanks for the hint regarding the gutters! Then we will probably have to plan a bit more money, since the gutters are supposed to reach the underground rainwater cistern..