Better buy now S23fe bro by just investing somewhat more amount. Coz s21fe is now very much old & its hardware now outdated, samsung also degraded performance & camera of S21fe very much now. After june-july updates s21fe camera became like 15k phone, u can see many user reviews here or any platforms & also battery drain like rocket, green line issue in this phone, u may regret after buying, so better go for s23fe OR s23 now
