It depends on what that milage is.
If it says 3,000 but looks like 20,000 then I would walk away.
Regardless if the milage is right or not, I wouldn't pay extra for low miles just because it looks like low miles. If it has higher than 10,000 miles It is probably OK.
If it is really low miles (like 3000 or less) I would have to wonder what kind of problems that scooter had that kept it from being rode much.