1 dollar bill from expo in Montreal what is it worth?

It depends on the specific details of the dollar bill and its rarity.

If it is a normal $1 bill that someone made a stamp or wrote Expo Montreal on, it is not typically worth much more than $1.

However, if it is a rare or misprinted bill, or has cultural or historical significance, it could be worth significantly more.

If you provide more details such as the year, type of bill (eg Federal Reserve Note), and any notable features, I can give you a more accurate valuation.