Think you might struggle with a a quad. Compare the width of the

tracks used by vehicles down near where the lighthouse track leaves

them. Quads have about a 4' track cars about 6' both leave two

parallel tyre marks. There only appears to be a single track about

the width of a single car tyre mark.

The answer then must be a donkey/mule/horse. Once well-trained perhaps it could be sent into town on its own with a shopping list.