Infinate $$$
This is my first hint so don't kill me if you think it's stupid. OK, first get 2 SP's, 2 Pokemon emerald games, and link cord.
Second Get one emerald game to have a secret base and a level 5 pokemon. Then get the second game to have a level 30 or higher pokemon. Third mix records with the games.
Fourth go to the first games secret base with your level 30 higher Pokemon and keep on battling the person you should get 2000 poke bucks each time you win.
Happy cheating!
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