A society is democratic when no one is so rich that they can buy someone, and no one is so poor that they have to sell themselves. Source: Internet
So live that you wouldn't be ashamed to sell the family parrot to the town gossip. Will Rogers
When you talk about a great actor, you're not talking about Tom Cruise. His whole behavior is so shocking. It's inappropriate and vulgar and absolutely unacceptable to use your private life to sell anything commercially, but I think it's kind of a sickness. Lauren Bacall
Plough your furrows deep while sluggards sleep, and you shall have corn to sell and to keep. American Proverb
To sell honey to one who keeps hives. Portuguese Proverb
It is no sin to sell dear, but a sin to give ill measure. English Proverb