Do you need a tour guide? Can you drive yourself?
For long-term trips, it is recommended to hire a car with a driver-guide: the local management of pastures, refueling rhythm, and weather at mountain passes is more stable. Self-driving is feasible, but one must accept transfers within scenic areas, speed limits, and night travel restrictions.
Chartered cars with a driver-guide are the mainstream option for long trips in Xinjiang: the local driver-guide handles road conditions, refueling intervals, mountain weather, and herds on the grazing paths, while travelers only need to enjoy the scenery. Self-driving is entirely feasible (with proper documentation and mountain driving experience), but you must accept three things: private cars cannot enter large scenic areas and must switch to shuttle buses, speed limits are strictly enforced throughout, and night driving on mountain roads and deserts is not advisable.