Construction financing questions for row houses

But in case of risk, couldn't the terraced houses including the land and our house, which have a significantly higher market value than the loan amount, be auctioned?

The bank is not interested in realization but in the loan being serviced.

which have a significantly higher market value than the loan amount?

The lending value is relevant. It is significantly below the market value. Calculate the total costs, the net rent after management and taxes, and see how attractive the investment is. And what you would think of it as a banker then...

For rental purposes, this project is uninteresting.
With at least €950,000 in construction costs including outdoor facilities and the expected annual rent, you are at a factor of 22 or higher.
The return is really not worth it.

If you want to generate cash flow, invest rather in dividend stocks or in an existing multi-family house that you can select according to its rental yield.

where do you see the mentioned mortgage lending value approx. here?

One more quick note. I consider the rental prices unrealistic...

You're not well placed here in the forum... Unfortunately, you are not allowed to provide references here in the forum. In the large social networks, there are real estate investor groups, I would ask there. You will surely find a financial broker who can help you affordably.