Own cost estimate - does it fit?

The shower is set to 36°, and the water always arrives at that temperature. Even if 5 people flush the toilet. It stays at 36°.

What a marvel of technology... that can definitely never happen with a heat pump and even less with gas... what a big joke.

For 5 people to be able to flush a toilet, there first have to be 5 toilets. I haven't come across that in a single-family home yet. And even if so, in a two-family house it's rather unusual for more than one consumer besides the shower to need water at all.

For the paving costing 10 euros, the substructure is still missing. The 40-50€ per m2 are quickly reached when you also need curbstones and concrete, tools, etc.