Plot in flood protection area - Not recommended?

Of course, it depends on the size. We can't know the situation on site and how big and long the slopes etc. are. 100 grand seems generally high to me. I would have expected something around 40 to 50. But it can vary so much. You need an expert on site to assess the situation.

Yes, it certainly can't be answered generally. Only maybe the order of magnitude. The slope, as mentioned, minus the 0.5 m retaining wall, is 1.35 x 34 x 4.4 m, then special foundations ... Without having considered any insurance contributions.

Besides, the question would also arise for me. How is one supposed to "replace" or compensate for the basement?

Furthermore, the question would arise for me as well. How is one supposed to "replace" or compensate for the basement?

How concrete is the plot? If you don’t have a basement, you build upwards or outwards. For that, you need floor area ratio and plot ratio, size of the plot, etc., to assess it. If you just wanted confirmation of your skepticism, I have to disappoint you. But if you don’t like the land, then just skip it altogether. We also had the option to build 20m behind a dike. Since I’m really averse to water, I immediately vetoed that. But I think we had more options here. Today, I wouldn’t be so stubborn about it anymore.

Do you have a hobby that absolutely requires a basement?

Storage space, for example under the attic. It doesn’t get wet and needs to be jacked up three times a year

Building services on the ground floor. Although it still takes up considerable space, it is smaller than the ones from the 80s with oil tank/wood storage, oil burner, hot water boiler, etc. And it doesn’t smell like oil

Make appointments with construction companies, preferably local ones, and let them spill the beans and give estimates

In this case, all the technology would go into the roof as far as possible at my place. It would be really bad if the flood comes and then the electricity, heating, and who knows what else are ruined.

Once again concrete enough to at least consider whether it is worth it or not. Still, you can't approach it any other way. The plot is approx. 550 sqm with a floor area ratio/floor space index of 0.4/0.8, 2 residential units but only a flat roof (so the attic is already ruled out). It's a new development area. I haven't checked in the development plan whether stepped floors are allowed.

Well, 0.4 is not bad at all. 220 on the ground floor and 220 on the upper floor - that would be over 400m². OK, you have to subtract the terrace and depending on what other extras the municipality might define there. But honestly, I think the area should be enough for the average consumer.