My other big point is to NOT RUSH to try to buy everything immediately. This game is meant to be played over several months. The map is HUGE. The reward as you go is to keep getting more and more property. It would be a pointless game if you just began with everything. Where's the fun in that? So start small, and savor the reward of working up to each new property.

That all being said, here are some ways I found that earn you cash quickly while advancing your game skills.

Ambulance Missions
You get the critical boost of extra health bar when you finish 12 ambulance missions - and you also rack up around $40,000 for that too. WELL worth the time, which goes by really quickly.

Grand Theft Auto San Andreas Walkthrough