Are the costs for the double garage set too high?

We looked at one of these garages and then decided to build a carport for half the price. We were not convinced by these steel boxes. It's somehow a cross between a garage and a carport. Definitely not suitable as a cellar replacement. And that would have been important to us.

Garage prices are totally insane...
We requested the same garage size (including foundation, installation, and submission planning) from over 2 developers and received 2 different individual prices despite the same manufacturer. Difference - significantly over the 3000 EUR mentioned here.
However, we also inquired on our own initiative and had to conclude that with 6x6.5 m without house connection we do not get significantly below 20,000 EUR.