Yeah, I’d look to see what restrictions Sweden has in place and how that’s working in practice. I can see maybe having “pay to play” fees for sports & extracurriculars, and certainly reasonable charges for cafeteria food, but probably don’t allow any other fees or other expectation of payment for books or registration or anything else.
(Charges for failure to return a book / tablet, damage beyond normal wear & tear, or late fees for library books the students checked out are fine provided that they are reasonable and in line with what a public school would charge.)