For a group of 12, the real question is luggage, not headcount. Twelve people with day-packs fit a 12-seater Tempo Traveller comfortably. Twelve people with overnight bags for a Coorg weekend do not — you'll want the 16-seater for the extra luggage space, even if a few seats stay empty.
The 12-seater Tempo is our most-booked small-group vehicle: AC, pushback seats, rooftop carrier, good for 8–10 passengers plus bags. The 12-seater Force Urbania is the premium upgrade if the group prefers a quieter cabin and a softer highway ride, at a higher per-day rate.
If half the group is luggage-heavy, skip the 12-seater and book the 16-seater — the price difference is small and everyone travels with their bags inside rather than stacked on the roof.
Get a transparent, all-inclusive quote for this trip — no surge, no surprises.