This exploit requires both a hard drive and a memory card to perform. This trophy requires you to beat the game with less than $100,000 in damage, no small feat. Have at least one completed game on the hard drive and start a new game using the memory card. Get to the first real mission (not the training one), then save and quit. Now, load up your hard drive save file and go to the final boss fight. Go into the options menu and go to the gameplay option and change the memory setting to the memory card save. Finish off the boss and the trophy is yours.