Can you calculate construction costs yourself?

It can't be rocket science. I have read up on cost groups, the construction cost index, etc... but what is the best way to proceed? Thanks GD

It is, because the framework conditions cannot be more individual than in house construction. Also, although theory is nice, it is useless as output for what you are looking for. It would be like trying to orient yourself on the standard land value when buying a plot. That simply is not the market price you actually pay. Theory and practice, indeed. This means that to estimate your individual costs you need offers. Without offers, especially at this stage, a realistic estimate is not possible. I would even go so far as to say that currently even the architect cannot realistically provide you with information based on experience values. So get offers in advance.