So there is a glitch in the game that I discovered yesterday that allows you to get infinite money.
I did this with Franklin but I think you can do it with anyone. Get on Franklins motorcycle and drive to a clothing store (preferably the Sub Urban in Alta). Drive the motorcycle into the shop. Kill the clerk and shoot the three registers taking the cash. You should get between 600-1200 dollars. Now get back on the motorcycle and back it out of the front door. Only go to the edge of the sidewalk then drive back in. The bags of money will regenerate in slightly different spots with different amounts.
You wont get a wanted level.
I know its not AS profitable as the underwater cash trick, but it works and thers no save load times.
Enjoy it while you can because I emailed Rockstar about it to have it patched, since this could definitely be abused in GTAO