You can download "100% Save Files" from sites like GTAForums to skip the grind and start with a full bank account.
Press R1, R2, L1, X, LEFT, DOWN, RIGHT, UP, LEFT, DOWN, RIGHT, UP . gta-san-andreas-unlimited-money-mod
Bet the on the horse with the highest odds (usually the bottom one). If you win: Go back and save your progress. You can download "100% Save Files" from sites
at a nearby safehouse (like the Jefferson safehouse). gta-san-andreas-unlimited-money-mod
Check out these quick guides for mastering money and more in San Andreas: