That is not only a lot of budget for excavator buckets, but also a noticeable impact on the groundwater level.
That’s just how basements are, right?
For this plot, I also currently consider the approach with the garage in the basement a good solution. It is too narrow and too steep to accommodate the cars elsewhere. You have to dig a hole for them anyway, and there is no space for switchbacks.
The question for me would be whether to make the basement, currently 295 cm, a bit higher? Of course, it’s a pity about the useless air, but then you get the south terrace a bit higher and have to excavate less there. That makes the space brighter, friendlier, and you’re not sitting so much in a dark hole. Naturally, you have to heap up some earth for that again. The excavation will probably not be sufficient for this. So, a costly paid seating area. Mmh, financially the terrace in the south is actually too expensive.