An easy method to achieve this achievement/trophy is to use the Hacker. This allows the player to "return" purchased perks for 100% of the cost. What a player could do is build up about 4000 points (the most for a perk), buy a perk, then use the Hacker to return it. This would return the cost of the perk to the player, allowing him or her to then buy more perks without having to obtain more points or down themselves. However, the perk Mule Kick should be the one bought last since it is located outside in an area without oxygen, making it very risky to hack and return to safety.