Originally Posted by
rickair7777
Yes they exist and are available. Expensive and impractical for anything but publicity stunts. Fundamentally, it's waaaaay more efficient to generate lift with rotors/fans (ie rotary wings) than with pure equal-and-opposite-reaction thrust.
https://jetpackaviation.com/jetpacks/
Note the price is not listed. If you have to ask...
found an AOPA article from 2018, they say 250k