New construction - How to build economically sensibly?

This is the house price including the land. Then there are the additional construction costs as usual, notary, taxes, land survey, etc. I cannot understand what is not to understand.

I don't either. But still, you are demonstrating it here. There is a good overview of additional construction costs here, a lot is included and you won't be below 30-40k there. And taxes and notary are not included and come on top of that. In your offer even significantly higher than usual, since they are charged on both house and land, instead of usually only on the land. You have to know all that, but then to claim here that with acquaintances only 5000 were added...

Don’t stalk around so much. Fact and realistic is, in the area Prenzlau Stettin there is a city villa with land for around 300 all incl. It’s like that. I think. In Poland, wages are often already higher than just west of Oder and Haff.

Ancillary purchase costs vs ancillary construction costs Are two different things. But this discussion is not about that at all?!

At winnetou there is a villa on a plot for 226000. that is correct. I have taken a look at our place. Comparable house approx. 470000. Plot is larger, it has to be larger with us too. Offer is more detailed, more extras included, better quality? ID: 91638617

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And that at our place - here building is still cheap!

I give up now.

How many times, 5000 EUR for additional equipment.

And notary, etc. belongs to my ancillary construction costs just like the electrical connection, etc. Why should I break it down again?