Shopaholic [Achievement]

Overview

Easy way.

Method

1) select the MP from the main menu
2) select character selection

here you will may not notice but there are two character rings for each faction. each containing locked characters and ready to buy characters. As a minimum to do this glitch you must have a character ready to buy in each ring (you will know because it has bolt/scrap icon attached to it not a lock) and between 36,000 – 40,000 parts of scrap. Make sure you absolutely do not purchase these characters yet. Also if you already brought a character this will still work.

(It’s easy with a joystick)
3) select a LOCKED character from any faction that you want to unlock
4) press triangle (swapping factions).
5) high light a character you can buy but DO NOT buy it
6) press triangle and cross (confirm) at the same time.

Now if all done correctly you will have swapped faction’s and be on the locked character asking you for confirmation to buy it. you can select yes and the requirment for the character will turn red taking the required scrap with it. do this till all locked characters on both factions have the requirments red then safely buy the already unlocked characters.
*The General character is no longer needed for this achievement.

7) press back to get to the MP menu then press back again and get to the main menu.
8) Close the game
9) Start the game.

Final note: the characters that you brought due to the glitch can not be used till you reach the level requirment. You will also not need to repurchase them at the unlocked level either.

Credit: [link]