Cost estimate single-family house KFW70 with approx. 135m2 without basement

The ancillary building costs should still be included with 30,000 euros in my calculation if I calculate the 5% real estate transfer tax, 6.5% broker fee, and 1% notary fee separately, right?

Your above-mentioned ones are mostly not even financeable.

Why?
Our bank included the construction incidental costs estimated in advance by the construction company in the financing. And I am not a single case, as I have read here in the forum.

Regards
Lilik

Why?
Our bank has included the building incidental costs estimated in advance by the construction company in the financing. And I am not an isolated case, as I have read here in the forum.

Regards
Lilik

Look here (quickly googled from an independent construction financing advisor):
"Calculating total costs for a new building project
When building a new house, it’s not just the land purchase price and the pure construction costs that matter. As the builder, you will face a number of additional costs:

[*]Real estate transfer tax: 3.5 to 5.5 percent of the (land) purchase price
[*]Notary and court fees for the purchase contract processing approx. 1.5 to 2 percent
[*]A broker's commission (if the land is brokered by a real estate agent)
[*]Incidental building costs (house connections, building permit etc.)
[*]Exterior facilities (garden landscaping, paving work etc.)
[*]Financing costs: Costs for land charge entries, fees, and so-called construction period interest
[*]Other costs: Costs for fitted kitchen, furniture, moving, topping-out ceremony etc.

Free Excel tool for calculating costs of new construction
For calculating total costs, we use a "simple" Excel spreadsheet that includes all conceivable costs that may arise in a new construction project. We are happy to provide you with this table as part of our consultation. We adjust this table together to your building project. You thus have an optimal "tool" to accurately and continuously calculate the costs of your construction project.
Not all costs are financed
Note: In the valuation by banks (for calculating interest conditions), only certain costs are included. Basically, credit institutions only consider costs that increase the value of the property. For example, individual financing costs or incidental acquisition costs are not included. Also, the fitted kitchen is not included by most banks in the so-called "reasonable acquisition and production costs" and is usually not financed.

Of course, there are banks that finance everything, even more than 100%. They then charge higher interest rates for that.

I meant the pure incidental construction costs such as house connections, building permit, surveying, earthworks, etc., all of which will be paid by the bank; approximately 30,000 are allocated for this. The other costs incurred when purchasing the plot (real estate transfer tax, notary fees, land charge registrations, etc.) will be covered by us. Just like the outdoor facilities and garage, although the bank was willing to cover those as well, it would have significantly exceeded our pre-planned limit.
Regards
Lilik

Hm we are currently planning too - my mother has built twice and said that for a 450sqm plot depending on the garden, around 10,000 to 20,000 euros are needed just for the garden with terrace and so on.

We need to slightly raise our plot because we have to compensate about 15cm of ground unevenness compared to the neighboring plots. I would say the budget is extremely tight, there are no big wishes in it and you always have to possibly factor in additional costs at least.