Is the dream of owning a home realistic?

It depends on the bank. With us, the loan amount is paid out without proof of invoices. So I could easily buy lamps, kitchen, etc., but I don't need to...

Very questionable... and are you sure they don't want any invoices?

They seem to live on a green island... a small savings bank?

Some posts here are "new" to me
It was the same with us as well. However, it had to be clear that the money was from the financing, which was also included in the calculation. For example, according to construction status reports to the homebuilder 200,000, the remaining 20,000 for ancillary building costs and outdoor facilities.
But of course, you couldn't just tap into something that wasn't included in the calculation from the beginning...
And I'll put it this way: with good equity, you can still choose the bank including the conditions. With little equity, you take the one that will go along with all of this at all.

So with a construction project with a general contractor or prefabricated house manufacturer... fine by me. The bank has already seen the contract with the description of services beforehand, so there's little "room to maneuver." But otherwise, I find that quite remarkable. That a certain portion is also paid out without an invoice is another matter. But it's supposed to be "alright."

Apart from that: We have included a point "Küche und Möbel" in the calculation for the bank; the bank will therefore probably pay us the money against an invoice for the kitchen or furniture. Especially when you have to provide equity first, these items remain at the end. Although we are not obliged to do so according to the contract, the vast majority of the equity is already tied up in the property for us.