Construction progress: Duplex with WU basement and developed attic

Compliment and great admiration from my side for how you are managing this and able to process it mentally and emotionally. I would probably have gone crazy and ended up in a psychiatric hospital. I mean it seriously.

Believe me, I was at that point too when I found out that GU1 had founded a second company and was completely fooling us. I was totally exhausted. I could only vomit, couldn’t eat anything anymore, was shaking all over my body, and was close to being admitted. How well I will handle it now remains to be seen. But I know that I have to make it and that there is no other way. That’s why I may react somewhat hypersensitively to some comments here.

If you know your stuff, that's the case.

What does "if" mean? When investing over half a million €, you have to know your stuff, meaning being able to evaluate and classify the prices asked. In any case, you must be able to spot extreme outliers of the normal distribution. With electricity, gas, and mobile tariffs (and probably also ice machines), it is no problem to assess an offer based on a market-standard price indication. If you want to.

he could have managed with 300,000 € costs and thus 40,000 €

So not even a 15% margin. You also seem to be self-employed. Would it be enough at a sales price of 50 cents per scoop if less than 7 cents difference between cost price and sales price before tax remain with you?
Of course not.

For electricity, gas, and mobile phone tariffs

Bad comparison, otherwise not every second person would be walking around with an iPhone and a 60 euro contract.

According to the offers available to me, he could have managed with €300,000 in costs and thus made a profit of €40,000.

€40,000 out of €300,000 is 13% for the general contractor to provide his services (planning, coordination, site management requires employees, vehicles, offices), bear the calculation, warranty, and inflation risks. From what remains in the end, he still has to pay taxes, and then he has the profit. Not much is left, neither absolutely nor relatively. I once read somewhere that a general contractor has to add 20% to make it work. No idea if that's true, but from €40,000 he definitely doesn't keep much, even if everything goes well.

€40,000 of €300,000 is 13% for the general contractor to provide his services (planning, coordination, construction management requires employees, vehicles, offices), bearing the calculation, warranty, and inflation risk. From what remains in the end, he still has to pay taxes and then he has the profit. Not much is left, neither absolutely nor relatively. I once read somewhere that a general contractor has to add 20% to make it work. No idea if that's true, but of €40,000 he definitely does not keep much, even if everything goes well.

As you may have already noticed, my general contractor has no employees, no office, and only one van. Furthermore, he cannot plan or coordinate, and construction management is a foreign word to him. That may be normal in most cases, but this is definitely not a normal case, as we have all realized by now.

So not even 15% margin. You also seem to be engaged in self-employment. Would it be enough for you if with a sales price of 50 cents per ball there is less than 7 cents difference between cost price and sales price before tax?

With 1000 balls a day, definitely. Oh damn, I actually sell soft serve.