Unenclosed vehicles are typically custom built vehicles (vans, box trucks, pick-up trucks) that are not occupied, meaning you do not stand inside the vehicle to vend. Food is prepared inside a protected compartment of the vehicle and served to the customer with no additional assembly or little extra handling required.
These mobile food facilities are operated much like carts but typically have more space and can hold more equipment, 3-compartment sinks, larger water tanks. They are still limited in the types of food preparation which is allowed, but can accommodate other such "limited prep" as coffee/espresso or waffles.
Please contact Environmental Health prior to making any financial investment in custom building an unenclosed MFF or purchasing one, especially from another State or County.