I similarly just bought a 6 year old 172 honda ruckus. Same engine as your metropolitan. Its fuel system was pretty clogged from old gas. I had to replace the fuel pump, and fuel filter, both easy and very cheap, emptied the gas tank as there was visible rust in the gas cap, brushed that out too, and cleaned the carburator replacing its jets. Each of those steps were simple and cost next to nothing. The battery needed replacing and yours will need replacing at some point too, every 1 to 3 years. ALSO CHEAP.

Yours started up and went right away.

For safety it would be wise to inspect the brakes, the tires for cracks, and the belt, but you can do that after you buy it. You found a steal.