Household Income vs Construction Costs

Regardless of the actual question, to which you have received sufficiently good answers.

Please reconsider the position 30,000 Eigenleistung.

30,000 Euro Eigenleistung at a generous 60/hour craftsman wage corresponds to 500 professional or 1,000 amateur hours. Evenly spread over 10 months, that is 25h/week in addition to normal work. And that is calculated very generously.

Please do not overestimate yourselves there, otherwise Karōshi threatens.

Ha, I had already calculated that in my head with €50/h and found it to be rather unrealistic...

You can also take a "more expensive" offer from the GU as a comparison - subtract the material and set the difference as the value of the EL. This admittedly results in a fairly high hourly rate for your own work ;)

1550 credit + 300-400 € incidental costs for the HAus (electricity, tax etc.).

What were you paying for rent before?

The additional expense compared to rent comes at the expense of saving (whereby you are then saving a house) or consumption (vacation in Hawaii, ski vacation, and eating out 5 times in a restaurant will no longer be possible).

I am only referring to the income and the monthly installment. We have the same income (bei einem Einkommen), also with two children, and our installment amounts to 1450 euros per month. We can live well with it, don't have to be super frugal, and can also build up savings.