New construction costs - Which house provider is financially feasible?

What do you think how many hours this in total were and material costs? Does anyone know the house provider Heinz von Heiden? He is relatively inexpensive.

200 sqm living space, shell construction approx. 125,000 euros

200 sqm living space, shell construction approx. 125,000 euros

Only for the material? That was then too expensive

Just for the material? That was too expensive then

I forgot to mention the garage here as well, 9x9m.
Still too expensive?

Forgot to mention the garage here as well 9x9m. still too expensive?

Yes Shell construction costs here in Emsland concrete/steel/bricks ~210€ m² materials only

Our shell construction (town villa, approx. 11x11m, two full floors + attic) including clinker brick (ground floor) and WDS (upper floor / knee wall roof) cost around €130k (built 2014). Both ceilings made of concrete, including concrete pedestal staircase.

Therefore: Yes, definitely too expensive!

I have been reading this forum for a year.
My advice: read many posts in the forum, especially regarding costs.
2. Visit model parks, compare prices and construction service descriptions. Everything that is not mentioned there is not included in the scope of delivery (price).
Alternatively, consult an architect, but clarify before the conversation what costs will arise when he starts working.
I would forget about building it yourself for several reasons, the main reason being time as mentioned by several here. Normally, you only have time on weekends, after work, and during several vacations.
A friend bought a house from the 60s. We did basic things like removing all tiles or wallpapering beforehand. The remaining work, such as renovating children’s rooms and bathrooms, has been dragging on for 2 years. He can and does everything himself, but eventually you run out of steam or simply lose the desire.

Is 150k€ equity available?
Why is a loan not an option for a new build? The land is already owned.