How much is a $1 bill worth?

Not much. Look, I'll trade ya for some old phones I got laying around. Ones got an IR blaster, would work great as an overly complex TV remote control that needs a proprietary connector to recharge.

$100 if you can bleach them.

Nothing, you should give it to me to dispose of

About tree fiddy

Last I checked you cannot sell Bill for $1. Also not for 1£

which one there's like 15 different dollars

With sales tax, customer service fee,
restaurant tip, service tip, tipping tip,
dating tips, Q-tips, Q&A-tips, time tips,
sugar tips, ..

$64.99

About a buck

SpaceX is worth 1800 billion dollars so around 1 billion is around 50 dollars.