A snake oil salesman: Someone who deceives others, especially by selling fraudulent or worthless products
Straight from the horse’s mouth: Information or news received directly from the original or authoritative source
Don’t count your chickens before they hatch: Don’t rely on something happening before it has occurred
A horse of a different color: A completely different matter or issue
When pigs fly: Something that is highly unlikely to happen
To be as busy as a flea: To be constantly busy or active