Are ancillary construction costs for a single-family house realistic?

Hello everyone,

my wife and I are currently in the early stages of planning our single-family house in Lower Saxony, which should have a floor area of about 170 sqm without a basement. To be able to first see what is feasible with our budget, I would like to realistically estimate the ancillary costs from the start. For this, I now need your help. I will simply list what I have planned so far and how expensive it will (or could) be and ask you to help me identify where my estimate is completely unrealistic or if I have forgotten something. We will not need an architect.

Ancillary construction costs in euros:

Plot incl. all ancillary costs: 58000
Surveying/cadastre: 2600
Soil report: 600
If necessary, plot clearance: 200
Building permit: 800
Review of construction contract: 500
Construction water/electricity incl. consumption: 1000
If necessary, earthworks (buffer): 2000
Development (electricity, water, gas): 7000
Insurances: 500
Construction period interest: 2000
Building expert: 2000
Outdoor facilities: 10000 - x ?
Carport/garage: 15000 - x ?
Kitchen: 10000 - 20000
Floor coverings and painting: 15000

Have I forgotten something or allocated significantly too much somewhere? Some positions like the kitchen etc. are of course very individual

Thanks in advance

If you do not have more precise information, the earthworks are probably insufficient. Connections are also missing.

Thank you for your reply. The plot is fully developed. I thought I had covered the costs for the connections under the item development (from the property boundary to the house). The plot is in a new development area where 5 parties have already started building. According to their information, they did not have to carry out any additional earthworks.

Earthworks are naturally a risk - depending on the ground conditions, it can be more (but doesn't have to be). Development costs somewhat depend on how long your driveway is. Generally, plan for a bit more. A building expert may possibly also become more expensive (depending on what you want). Outdoor facilities depend on the start of your property. Kitchens should cost between €10,000 and €15,000 if they are not meant to be too extravagant. You don't need €15,000 for a carport.

If you don't have more detailed information, the earthworks are probably insufficient. Connections are also missing.

I overlooked the development.

Thank you BeHaElJa, yes the building ground is a risk, I have that in the back of my mind. I suspect that it will be between 5 and 7 meters from the property boundary to the house. Unfortunately, I have no idea about the outdoor facilities yet and it is supposed to be a carport-garage combination... so the garage slightly offset from the house and the space between the house and garage then covered as a carport. Regards