I’m bought a secondhand-good as new FP3 thirteen months ago and have been using it since, first running DivestOS and now running /e/OS. It only cost me 100 €. I can squeeze almost two days of battery if I the only thing i do is check messages and e-mail with all non-essential services disabled. Otherwise, with regular usage scrolling Lemmy, browsing news websites, checking messages & e-mails and watching the occasional video my battery will last for around a day