Taxi hint:

Get a taxi. Select the taxi driver mission. Complete 1st fare AND, wait! Go collect
next fare, but make sure he/she close car door on end of 0:00 second! Now you gotta
unlimited time for all next fares. Trick is over when you cancel taxi driver mission
or exit taxi vehicle. Thing is really hard to do, but once you did it, all will be
easy. Note I used cabby for this trick, not normal taxi car.