ᐅ Construction of a driveway using gravel, crushed stone, and paving stones?

Hi everyone,

What is the recommended construction for the subbase of the driveway?
Our excavation contractor will be back soon with the excavator to install the utility lines. At the same time, he will level the driveway to the correct height.

His rough rule-of-thumb suggestion for driveable surfaces:

25–30 cm (10–12 inches) crushed stone
5 cm (2 inches) gravel
8 cm (3 inches) paving stones
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38–43 cm (15–17 inches) total build-up

His rough rule-of-thumb suggestion for pedestrian paths:

15 cm (6 inches) crushed stone
5 cm (2 inches) gravel
8 cm (3 inches) paving stones
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28 cm (11 inches) total build-up

The foundations for the carport are already in place and are significantly deeper. This buildup would only apply to the paved surfaces.

Does this seem reasonable?

Thanks and best regards,
Andreas