I buy paperbacks, chop and scan them [1] then use a reMarkable tablet + RCU [2] to do the reading.

Digitizing paper books and writing on them with digital ink is 100% the best way to have marginalia. I've tried special dotcode pens, portable scanners...writing digitally with a stylus is the best. Yes, it destroys the paper book, but it more than makes up for it with the freedom, flexibility, and durability of the digital copy.

[1]: https://www.davisr.me/projects/books/ [2]: https://www.davisr.me/projects/rcu/