Surface for the driveway?

I'll join in with a question here:

How deep should the driveway/parking space be excavated? Or are different excavation depths required for different surfaces?
Currently, I'm considering a gravel option (because of infiltration). Maybe later with the option of permeable paving.

The question would also apply to the terrace right away. What excavation depth is advisable there?

Thanks!

What is a gravel lawn?
Well, we have coarse gravel, also called crushed stone. Beautiful granite-colored, elegant. It has nothing to do with lawn.
Everything soaks away. It was cheap, too.
Because it is so great, we also added a 1.50-meter-wide spray protection path around the house at the same time.

Snow doesn’t stay on it. End of story. Everything around it is green – for the bees and me

This is basically the water-bound surface I mentioned, except that PU is added here as a binder. Otherwise, it is a compacted mixture of grit/gravel.

Do you happen to have any experience with it yourself?

Hello, could one maybe see pictures of your driveway? And maybe how the word "günstig" is defined? We are considering filling our almost 30 m driveway with the coarse gravel as well, hence the question.