The Short Answer
A private Mutianyu Great Wall day tour with guide and car typically runs $389-553 for 1-2 people, roughly doubling per added traveller up to a point. A private day combining the Forbidden City, Summer Palace and a lake cruise runs $605 flat for 1-2 people. A private day trip to Chengde (a longer-distance site) runs $535 solo, stepping up with group size. A multi-day private tour (4 days with guide) runs $1,709 solo, scaling roughly linearly per added traveller since it includes extended guiding time each day.
Beijing: Mutianyu Great Wall Private Tour & Cable Car
A real example of standard private day-tour pricing with guide and car.
From $389
Full day

