New single-family house 180m²

Hello everyone,

I am new here in the forum and would like to discuss with you an offer from a prefab house provider:

[*]Location: Heilbronn district, BW
[*]Plot: 636m², slight slope
[*]Single-family house, 1.5 floors without basement, 181m² floor area, Kfw55 envelope, gable roof with 30° pitch

We have received a detailed offer and would be interested in your price assessment (prices are excl. VAT):

[*]Building application/calculations/statics: €5,000
[*]Construction site setup, scaffolding, truck crane, work planning: €11,250
[*]Base slab (DWD base slab 25 cm + 8 cm Styrodur insulation under the base slab): €20,600.00
[*]Carpentry work (wall build-up: 60 mm wood fiberboard as plaster carrier, 240 mm timber frame construction with 240 mm rock wool insulation, 0.2 mm vapor barrier paper, 12.5 mm gypsum fiberboard): €93,000
[*]Roof covering: €5,250
[*]Tinsmith work: €7,600
[*]Windows (plastic, white inside, foil coated outside, triple glazing) and front door: €22,700
[*]Shading (13 aluminum roller shutters, 4 rail-guided, electrically operated venetian blinds): €7,800
[*]Heating (air-water heat pump split unit without ventilation system): €25,000
[*]Sanitary installation (3 washbasins, 2 WCs, 2x walk-in showers, 1x bathtub): €13,500
[*]Electrical (standard, no KNX etc.): €12,000
[*]Exterior facade: €14,500
[*]Screed: €7,600
[*]Tiles (material: €35 per m², 32m² wall, 101m² floor): €12,800
[*]Floors (51m² laminate up to €37 per m², parquet 29m² up to €60 per m²): €6,450
[*]Interior doors (real wood veneer): €3,800
[*]Staircase (wood, folded design): €12,600
[*]Painting and plastering work (painter‘s fleece): €16,500

Total: €297,950 excl. VAT equals: €354,560 incl. VAT

What do you think?

Thank you very much for your opinion!

Best regards

Everything always including installation?
Sanitary could be more.
Electrical as well.
How many doors are there?
Wall without installation layer? 1.25 cm plaster - is that okay as an interior wall? (I’m not very knowledgeable about that, would be skeptical).

The final price could be right, the distribution might be a bit off, don’t you think?

20k for the base slab but where are the costs for the foundation, disposal, etc.?

Air-water heat pump without heat recovery? Or what do you mean by that?

Yes, everything including materials and installation. There are 8 doors - one of them is climate class 3 (installation room due to soundproofing). We have 21 windows, see window list. Yes, the walls currently have no installation layer. That would be an additional cost factor. How do you see that in terms of insulation, etc.?

: I do not have a price yet for the foundation, it is listed in the offer as follows: For the static and frost-free foundation of the house, either a gravel bed or foundations under the floor slab are required. The quantity, size, and height of the required gravel bed or foundation can only be determined and offered after completion of the building application and exact terrain survey.

Heating is:
Tecalor TTL 15 ACS (air-water heat pump) for outdoor installation including WWS TSB 301 heat pump and buffer tank TSP 200
Heating: YES
Hot water: YES
Ventilation: NO
Cooling: NO
Hot water tank: 300 liters
Additional buffer tank: 200 liters
Max. heating load: 8.8 kW
Max. area for underfloor heating: 220 m2

Still living in an old building, so no practical experience: The ventilation system seems necessary to me. Kfw55 houses are so airtight that airing through windows hardly makes sense. Besides, kfw55 is not achieved.