Disk Space Full Achievement.

This guide will help you to get 3 songs only (Blvck And White & Dark Steering & Ms. Crumby) by hacking 3 people, it's RNG so will take more time to do, first you can use this guide for other songs:
https://www.playstationtrophies.org/forum/topic/221395-media-appsongsneak-guide-disk-space-full-trophy/
its so simple, just follow this route on feet ofc, do not hack bank account will distract you, at the end of the route you can go more forward if you see more NPC if no luck or you get one just exit to main menu and retry, i do not know if time affect just in case i did it in daytime, it take me 7 runs to get all 3, good luck.