House for just about 1300 € per sqm???

... we decided on a prefabricated house with 148 sqm. According to the brochure, the base price for the house was just under 114,000 euros. After selecting some extras such as a conservatory, KFW55 standard, and underfloor heating, the next appointment provided the calculation.

As personal contribution, we want to do the drywall, lay laminate/tiles, install interior doors, paint/wallpaper, receive materials, and install sanitary fixtures.

- Fees such as notary, construction electricity, etc. 6000 EURO
- House connections 6000 EURO
- Gravel bed (groundwork) 6000 EURO
- Surveyor is included in the house price

This effectively means a price including incidental construction costs of 198,000 EURO.[...] Now I always read in the forum that a house costs at least 1600€/sqm... at that price we would be at 1216 €, including incidental costs at 1337 €. So I wonder where the catch is!?

Hello, my name is Martin and since my girlfriend and I want to build a house, we have already been to a producer of prefab houses (I don’t know if advertising is allowed here, so I’ll leave the name out for now) and got some advice there.

Since we both have relatively little experience with house construction and the current prices, I registered here in the forum hoping to get some advice from you.

After the first consultation appointments, where, as usual, a lot of sweet talk was given, we decided on a prefab house with 148 sqm. The base price for the house was according to the brochure just under 114,000 euros. After we selected some extras like a conservatory, KFW55 standard and underfloor heating, the next appointment gave us the calculation.
I would like to briefly list it:

- House price €180,000, including:
- Flat rate for plan changes (we can modify the floor plan)
- all architectural services (building application meeting, approval planning, surveying services, statutory construction supervision)
- Exterior plaster
- Gutters and downpipes in titanium zinc
- Roof covering with concrete roof tiles, Finkenberger tile
- Front door in white plastic
- all windows/terrace/balcony doors with triple glazing
- Solid wood staircase (made of core beech finger-jointed)
- Floor slab according to KFW55 standard
- Heating (standard gas condensing boiler), controlled ventilation system with heat recovery
- Underfloor heating
- Conservatory
- Solar system flat collectors (300 liter water storage)
- Materials for drywall construction, electrical installation materials, heating system, home technology, piping
- Materials sanitary objects, tiles and window sills, interior doors, flooring (laminate), wallpaper and paints
- Labor: laying the floor slab, screed, electrical, sanitary rough installation, ventilation system and heating system, conservatory
- Tools for self-construction

As personal contribution, we want to do the drywall construction, lay laminate/tiles, install interior doors, paint/wallpaper, receive materials, and install the sanitary objects.
We leave the plot (including acquisition tax) out because the price depends too much on location; we were given the following projected additional building costs:

- Fees such as notary, construction power etc. €6,000
- House connections €6,000
- Gravel bed (groundwork) €6,000
- Surveyor is included in the house price

This ultimately means a price including incidental building costs of €198,000.

Now I always read here in the forum that a house costs at least €1600/sqm... with this price we would be at €1216, if you include the incidental building costs at €1337. So I wonder, where’s the catch!? Of course, we still plan about €10,000 as a buffer for a slightly nicer interior finish, but basically no significantly high costs should come on top of that, right??? Can you help me with this?

Thanks a lot in advance