Own cost estimate - does it fit?

Good evening,

Single-family house, 170 sqm, 2 stories, flat roof, simple design, KFW 55, no basement, monolithic construction, masonry double garage with space for garden tools, bicycles, trash bins. Photovoltaics approx. 4kwp, geothermal energy with ground collector.
Garden initially with necessary paving work and lawn seeding.

170*1600 = 272,000 house
8,000 photovoltaics
20,000 floors and painting
40,000 ancillary construction costs
25,000 garage
15,000 garden

Total of 380,000€ plus land and purchase incidental costs, furniture (kitchen), moving and the like.

Is that about right?

No.

As a previous poster already wrote, the geothermal heat pump cannot be included in the base costs you posted; nobody gives anything away for free. The costs for photovoltaics also seem very optimistic to me; the same applies to the estimated costs for the masonry garage. Furthermore, I am missing the surcharge for KfW 55.

What saving potential would there be regarding the garage, e.g. a corresponding carport?

A prefabricated garage; a good carport is not really cheaper than a prefabricated garage. But it is significantly cheaper than a masonry garage.

Is an air-water heat pump significantly cheaper than geothermal energy with ground collector (probes probably are not possible)? We don't like air-water heat pumps much because of looks and possible noise issues.

The air-water heat pump is a Jehovah topic here in the forum. It is roughly comparable in cost to a gas condensing boiler with a solar system for domestic hot water heating. If you find a good provider, neither noise nor appearance is a problem.

@@Bauexperte
You are almost active in the region – what do you think?
Happy to discuss via PM ...

Feel free to contact me via PM, and then we will see how and if I can help you.

Rhenish greetings

So, the photovoltaic system may be ambitious for the price, yes, but not impossible. We paid 10 for 5.4 kWp and had to raise it on racks... so 4 for 8 on a pitched roof I see as unproblematic.

In relevant photovoltaic forums, a kWp price of €1500 is being discussed.

Bigger cheaper, smaller more expensive...

If you want to work with geothermal energy, google "geothermie NRW". The Geological Service of the state NRW has a tool that allows you to roughly estimate the yield or efficiency. This is not always possible everywhere.

You can also call the gentlemen from the office and ask - they are very helpful (at least they were for us in Lower Saxony)