Cost explosion even before it really gets started

I am not a layman. I am not a layman. I am not a layman. I am no..

You noticed early on that something was wrong, but did not act accordingly. From now on: clear statements instead of questions. Do not sit out problems.

We had to learn this too, similar situation with the architects.

No one acts entirely in your interest. Some things go well, some do not. Everything you can take care of yourself will be better than if it falls from the sky.

Domski’s advice to hire your own expert for the construction phase I can only emphasize. And please don’t complain there, but give a mandate.

Honestly, I find it shocking that if you hire an expensive architect, you now also have to pay for a supervisor. Madness.

Honestly, I find it shocking that when you hire an expensive architect, you now also have to pay a supervisor. Madness

That's only because he got the wrong one!
The worst are those from the close circle of friends or acquaintances because you trust them the most.

I've read this dozens of times here. We once had someone who the OP knew from the tennis club. After they had a falling out, the architect wanted to bill according to HOAI afterwards and was allowed to.

The architect is the client’s advocate. If the architect messes up here, please don’t add extra supervisors, but say: I pay you to listen to me and do as I want. If it doesn’t work, please say so. - And ultimately, the client approves the orders, not the architect. If the client signs orders that lead to their ruin, it is simply just stupid.

Yes describes the role of A very well. Because I would activate extra construction experts if the senior A continues like this. Then I would dismiss A and continue with an experienced engineer. This was not clearly written in the original post.

Financial framework currently is 300,000 + 25% reserve = 375,000€. Cost projection currently 350,000€, END OF STORY is already in sight here. Before it is clear to what extent additional financing would be possible, there is only one logical consequence: construction stop!

Otherwise, the money will run out in the final phase. It makes no sense now to make "clear statements," to have offers "shown beforehand," to "read books that turn laypeople into experts," or to bring a "construction expert" on board, your tips will NOT immediately solve the foreseeable liquidity problem.

A new concept is needed here.

1. Clarify the budget framework again: squeeze family, explore additional financing, raid assets/pensions, sell family silver. In the worst case, it stays at 375,000€, but in any case:

2. Replan the project and "garage gone" is not enough here. I mean, you’ve seen the cost estimates, some items are a joke: bathroom incl. rough installation 8,000 + VAT,... complete electrical 12,000 + VAT, come on, stop... what is there to say? Roofing 90sqm 10,000€??? Of course including shaped stones/verge stones, underlay membrane, funnel sheets, gutters, roof clips, consumables etc? Just the roofing plumber work, labor, travel,... how is that supposed to work? From the current 350,000 a realistic 450,000 will come if something fundamental is not changed now.

...no, and the architect seems to have seriously implied that one would get a high-end standard here? I suspect, for some items, a factor of 2 or 3 or even ... 4

3. Present the new planning here in the forum, here people who are currently going through it themselves know what is realistic and what is not.

Ps. If there really is a roofer who covers 90sqm completely with materials and everything for 10,000€, please definitely forward the phone number to me!

You can also overdo it with the uncertainty... For us, 160 sqm of roofing with counter battens, roof battens, underlay membrane, roof tiles (lifted) cost almost exactly 10,000 net. The comparison quotes were at the same level.