Check your local Tractor Supply for returned Champions. We find them every few months that "won't run" and buy them cheep.
The Champions have a low oil shutoff and they don't ship with oil. So many folks try to use them without reading the owners manual, get frustrated, and return them for another brand.
Other times we've had to but new carburetors because the cheep gas has eaten away the seals. Only put ethanol free gas in your generators and other gas powered equipment. I've seen how sitting with regular fuel will eat away the rubber in a mower.