Check cost estimate from preliminary draft

For "normal" renovations involving a little wall removal, I simply don't know anyone who goes the whole way with an architect

Yes, unfortunately this is widespread and costs the corresponding tuition fee – lucky are the cheerful souls who don't even notice it. You can need an architect for every modernization or even renovation: connection details, i.e. interdisciplinary detailed drawings, are not exactly the domain of individual craftsmen. And construction management and scheduling are no less important in existing buildings than on the "blank slate" of the "greenfield".

Then I'll just elaborate a bit more: We had 2 children, then came twins again (jackpot!). So now we are 6 and actually need two more rooms for the little ones. Since our attic so far is a cold roof but has about 90m² of floor space (thanks to the mansard roof!), it made sense to create additional living space there and, in this context, of course also insulate the roof. Since the rest of the house is so far uninsulated, except for some interior insulation from ages ago, we decided to have the windows and facade renovation including facade insulation done at the same time. Naturally, also replace the front door and renovate the ground floor bathroom, which radiates the nice white and red charm of the 80s. Additionally, our plan now was to place the children's rooms on the first floor and design them to be as equivalent and equally sized as possible. We would then move into the new attic. In order to receive the KFW subsidies, our architect plans to insulate the floor on the ground floor in the area that is not cellar below. In the cellar area, he plans 8-10cm thick ceiling insulation. Unfortunately, our trust in the architect is no longer very great due to many small sloppinesses / forgotten things, hence the request to review his cost estimate...

Addendum: As I read in the other thread, for example, the 5% from the renovation plan planned by our architect only exists if you have at least two steps. However, we would like to carry out everything at once, so the 5% subsidy would, for example, be incorrectly included in the cost estimate.

Addendum: As I read in the other thread, for example, the 5% in the renovation plan planned by our architect only applies if you have at least two steps. However, we would like to carry out everything at once, so the 5% subsidy would be incorrectly included in the cost estimate, for example.

That is two steps up to the maximum, right? If you renovate to KfW 70, then you are not doing "everything at once," are you?

We would like to do everything at once,

... to then be guaranteed ready for the island?

By "everything at once" I mean that we carry out all the work over a period X. We want to get everything done in one go now, instead of having the construction site forever. I don’t mean that in two weeks (for example) we should do roofing / interior work, basement insulation, exterior insulation, doors, windows, upper floor renovation, ground floor renovation all at the same time. Of course, that will be "scheduled."

The idea is to start, for example, with the attic and then work downwards, depending on what makes sense, so that there is always some "construction-free space" available for the children.

Another point why we want to have it planned by an architect...