eBay does sell used outboard motors of all sizes and horsepower. Yamaha, Nissan and Honda are a few brand-named outboard motors available on the site, as of June 2015.
As of June 2015, eBay has outboard motors that range from 10 to 200-plus horsepower. There is also a variety of styles available, from the most modern engine to vintage motors. A shopper can use the advanced search options on the eBay toolbar to set up a search to return results that match the desired criteria. For example "Brand," "Condition," "Price" and "Engine" can be narrowed down to provide a more narrow search for a shopper.