Phone Recos >12k

Looking for phone recos under ₱12k

Main specs I’m looking for: Android 15+, decent battery (yung kaya sana buong araw on one charge), plus na lang if 5G.

Currently considering a secondhand Honor 400 5G, pero medyo nag-aalangan ako sa used phones since di ako sure paano properly i-check if legit/original, battery health, history, etc. 😭

Any recommendations or tips for checking secondhand phones? Tyia!!