.So, in looking for a new way to make some money last night (since my cars decided to poof and Violent Duct was no longer a feasible option), I may have found a nice little money making option that also allows you to unlock locked car parts and made quite a bit of Rank Points:
It requires at least you and one other person, although we did it with 3 people total this morning. Hit the start button, go to the Jobs section, go to Races. In the Races section theres a race called "Take Off" or something like that. It's essentially a figure eight, flat race at the airport with no obstructions and it takes 1 minute or less to complete the lap. Now, set the number of laps to 1, and make the other race settings favorable (Good weather, midday, no traffic, etc). Invite a buddy to join you to the race. Pick one person to win the race ahead of time. That person bets $2500 on themselves, while the other person bets $100 on their own car (Yes, that racer will lose that money). Complete the fixed race. The winner will get about $3700 for a 1 minute race ($4600 I think for 3 people), plus $1000 from winning the bet. They'll also get credited with a race win, which helps unlock parts. You'll also get anywhere from 600 RP (Last place) to 1200 RP (3 person race). The best part? You can replay this kind of mission from the voting screen (This is after patch 1.03 too).
One note - if you're doing 3 people in a race, two people can bet on the fixed winner beforehand and both make money, but at least one other person will have to bet on a loser. If everyone bets on the same person then all bets get disabled (Rockstar must have foreseen fixed races).
Try it out with a buddy, let me know if you guys like it. It seems like a lot of text there, but once you get in a rhythm you can knock out a race every 2 minutes roughly (If you add in loading and such). With 3 of us racing and alternating wins I was getting $10,000 after the 3 man race rotation and we were doing a new race every 2-3 minutes. I also went from Rank 30 to 42