To buy all of the game bonus content you will need 90,050 points. I would wait until after you have finished the story and have upgraded all your weapons and abilities before buying everything. The film and game bonus content will be found at the main menu in the garage.
If you are like me, you probably did not have enough points after the final level to buy all the bonus content. If you need points then I would recommend replaying levels that you know you did poorly in.
If you want to conserve time and not deal with the bosses, I would recommend replaying each of the levels that don't have a boss. The levels without bosses would be: Prologue, 1-1, 1-2, 2-1, 2-2, 3-1, 3-2, 4-1, 4-2, 5-1 and 5-2.
Your achievement will unlock once you have bought everything and exited the garage.
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