I can’t see how there would be any cost savings except if you dump equipment that would otherwise be available; making the entire contents of a clinic mobile is surely more costly and complicated than paying rent.
Test kits are mobile, vaccines and bloodwork are mobile, basic diagnostic equipment is mobile. Most people do not need the vast majority of things a clinic contains; nothing you couldn't solve with a small refrigerable unit in a vehicle.
That being said, the downsides of travel time are so negative it's hard to see how they could be overcome.
That being said, the downsides of travel time are so negative it's hard to see how they could be overcome.