we are building ready for finishing with a developer
I do mean a developer, it is the company
It's not about which is the correct term.
Can you please define a developer for me?
If you had read #2 properly, you would know the definition and the rough difference. I will have to delete tox’s link again, but here is my excerpt from #2:
With a developer you purchase a piece of a house and only become the owner once it is finished; with the general contractor you are the builder yourself, the company coordinates the house that you have commissioned.
I’m just surprised that when the company commissions a subcontractor for a service, such as digging the pit for the base slab, this subcontractor charges me any costs.
You specifically hired a general contractor so that you don’t have to coordinate and commission every craftsman and every order yourself. The general contractor takes care of that now, still you have to pay additional costs for extra services according to your work contract and the construction service description.
I have the feeling that you did not properly inform yourself before approaching the topic of house building, found a builder and signed blindly – of course with the background that the builder is very cheap. You surely did not review the services.
Certainly, the removal of the soil is rarely included in the price; it is usually described as follows:
Excavated soil is stored on the property and redistributed on the ground after the shell construction.
Nevertheless, you should now check for yourself what else might “surprise” you.