The decision is not based only on how many cases you have
Two equipment cases can mean very different things. Some travellers carry only a camera body and a few lenses. Others add a long lens, tripod, drone, batteries and hard protective cases. In the second situation, the vehicle may still close, but passenger legroom, aisle movement and access speed are already compromised. The real question is whether the vehicle remains safe and comfortable, not whether the boot technically shuts.
Frequently used gear should not be buried under everything else
Xinjiang photo stops are often short, so access speed matters. If the group must unload ordinary luggage first every time the photographer wants the main setup, the vehicle is no longer organised well. Once a piece of gear needs repeated access during the day, it deserves a more direct position and sometimes even a dedicated seat.
When gear starts shrinking family comfort, it is no longer a minor issue
This problem is often underestimated on mixed family trips. If a child's foot space is blocked by camera bags, a senior traveller must step around a tripod, or basic in-cabin movement becomes awkward, the space has already been overused. Continuing with a “we can manage somehow” approach usually makes the next several days worse.
Use three thresholds to decide on a seat or a larger vehicle
Ask whether the gear already takes away meaningful passenger space, whether the rear luggage area must be reopened many times a day, and whether fragile or expensive equipment cannot be stacked safely. If two of those are true, do not plan the vehicle as if every passenger seat should stay occupied.