Comparability of costs Architect vs. General Contractor

I have almost always rejected the general contractor because they are inflexible after signing the contract.

Against the architect: having to spend quite a bit of money without having moved a single blade of grass.

These "late decisions" or changes are definitely more stressful than with the general contractor but manageable without major financial expenses.

When we went to the architect for the first time, he took out a book labeled BKI - to give a rough estimate of the feasibility of the construction project based on this information. He calculated roughly 3,000 euros per sqm and 150 sqm of living space, resulting in a total of 450,000 euros.

What is included in the architect's 3000€? What about in the general contractor's offer? Basement, foundation slab? Earthworks, sewer? Utility connections? ...? 3000€ for a house on a foundation slab (without earthworks, etc.) sounds quite realistic at first, but in the end you have to compare apples to apples and pears to pears. This means that as the client you are obliged not only to compare the offers based on price but also on scope, and to calculate corresponding deductions for services that are included in only one of the two offers/estimates. That is the point you need to consider; the fee comes only in second place.

An architect does write out the specifications, but with some bad luck, you end up with an (unknown) craftsman who is "bad" despite defined performance.

The architect, however, has good references, let's see. It's just a small planning office in the city where we come from.