Electricity bill extremely high due to heat pump malfunction?!

Where does the knowledge that you have incurred €1000 in damages come from? You probably don't have any comparison values, since this is the first season. Household electricity on the same meter? That makes it even more unclear. So that would also be up for discussion.

House electricity and heat pump fortunately have separate meters.

The 1000€ are really worth it; six identical houses were built at the same time, and in the same period we have about 1000€ more than the other five, and I am sure that we would have even less than the others, but in this case that wouldn't matter and is also not provable.

Ok, writing it down doesn't even sound wrong, I should consider that.

In the beginning, it was very stressful.
By now it is calmer but still stressful. Since we bought all the furniture in the whole house new, we would have trouble and running around with all the companies.
Besides, both fully employed and the change from a 50qm apartment to about a 200qm house was first unusual.

So I will start noting that down for the future.

You can try to draft the appropriate letters; without legal protection, I would save the lawyer visit and share the Bacardi with you using nordlys.

Exactly, I'll pay for Coke, he Bacardi. As a bonus, I'll also cover ice and lemon. Cheers.

I wouldn't donate or bet on anything, but I would definitely join in on the drinking binge :D