Cost of construction of access road and removal of excavated soil

Knowing or not, there are still more factors that play a role. Whether it is the time, or the skill. If something is not done correctly, it has to be reworked by a professional in the end, or, or, or...

Apart from that, is digging out 30cm enough, or 50, or something in between?

How much expertise do you really need? Everyone nearby has Boels as a rental company for work equipment. Even better are local providers. And one phone call later you know which material you need for a construction road and you also know the price.

Anyone can also operate a vibrating plate.

Don’t let the general contractors rip you off all the time. They count on the convenience of the builders.

Well, I also belong to the "convenient builders" and wouldn’t trust myself with something like that. As already said, you also need time, experience, etc. Certain things simply have to be done by professionals. That runs through the entire house construction. For sanitary, I also pay much more for the sanitary objects than for example at the hardware store, because I can’t install them myself or it would just be botched.

Whether you know or not, there are still more factors that play a role. Be it the time, or the skill. If something is not done correctly, it has to be reworked by a professional in the end, or, or, or... Apart from that, is 30cm excavation enough, or 50, or something in between?

I think for us it was 30 cm, but that should be decided later depending on the load (crane, 40t truck, etc.).

And depending on what kind of ground lies beneath the gravel.

Comfortable is something else than not trusting oneself.
I also did the move comfortably. People pay and watch others carry my crap. I liked that.
Trusting oneself is something different. In the end, it’s about removing soil, putting in material, and compacting. Anyone who can use a shovel can do that.
Time is YET another thing. Not everyone can take the time.
And then there’s the price/performance calculation. Depending on how much it is, I wouldn’t do anything myself for a €1500 saving either. But eventually I’ll be too stingy for such simple tasks.
It has nothing at all to do with electrical or plumbing installation.