Are the construction costs calculated so solidly?

Hello,

I am new here and would first like to thank everyone who takes the time to provide help!

We are planning to build a single-family house (timber construction). Our calculation without the land looks as outlined below. I would be interested in how realistic you think the numbers are or if we have forgotten something. I would also appreciate feedback on whether you think the buffer is sufficient. Many thanks in advance!

1. Earthworks (excavation, inspection shaft, connections for water..., disposal, gravel): 15,000 euros <-- according to expert estimate somewhat cheaper
2. Outdoor facilities (driveway, approx. 15 meters through the garden, parking space, initial garden work): 17,000 euros <-- company estimate
3. Ready garage (7m length): 12,000 euros <-- fixed-price offer
4. Additional connection work (telecom, construction electricity): 4,000 euros <-- estimate by architect
5. Construction electricity and water consumption: 2,000 euros <-- estimate by developer
6. Architect: 6,000 euros <-- known figures
7. Permit (notification and surveyor...): 4,000 euros <-- known figures
8. Wooden terrace: 12,000 euros <-- estimate by provider
9. Built-in kitchen: 15,000 euros
10. Furniture, lighting: 8,000 euros
11. Other small items outside: 2,000 euros
12. Buffer: 10,000 euros
13. Timber house: 310,000 euros <-- fixed-price offer completely ready to move in
14. Wishes for slightly more expensive parquet flooring and sanitary fittings: 4,000 euros
15. Two basement rooms at own expense tiling (cheap tiles from hardware store) and painting (approx. 50 sqm floor area): 4,000 euros
16. Insurance, topping-out ceremony, etc.: 1,500 euros
17. Small items inside: 1,000 euros

I would say the two basement rooms can also remain as is (shell construction) if it gets really tight. The prices so far are without any own labor, but some can still be done by ourselves. I also hope that the kitchen might be available somewhat cheaper, we’ll see. Some figures were estimated a bit cheaper for us, but we have calculated rather conservatively. So these are also "small" buffers in the financing.

What do you think about the numbers?

Who is supposed to answer that? Without knowing the size and without a ground survey, this cannot be assessed. I am missing costs for water and electricity connection.

Do you have more detailed information or plans regarding the house and the property?

Hello everyone,

so it is a plot of land with a size of 823 sqm in southern Baden (slightly north of Freiburg). I probably expressed myself incorrectly. Of course, no one can say anything about the individual numbers without detailed information. I was rather concerned with the question,

-whether fundamentally important items have been forgotten,
-whether the buffer including the options is in a healthy ratio to the other numbers,
-whether the numbers are basically realistic (although this is of course hard to say, obviously!)