Sounds like a dream job or a nice side gig if you just want a job. Login, run script, log out, bill for thousands, then go back to doing your own thing.
Intentionally withholding stuff without offering an upfront option is shady though.
Where do you draw the line? My grandma was once contacted by a scammer who offered to "optimize" her laptop, and she ended up paying roughly the same as the price of a new laptop.