Easy money: Go to Bruski's Scrapyard. There is a random car located next to the car crusher. Break into the random car. You do not need to pick the lock because there are no cops nearby. Drive the car into the car crusher, and crush it to get approximately $400. Get in the car you came in, and drive it out of the scrap yard using the north exit located on the map. Travel this road until you go under a bridge. Then, turn around and go back to the scrap yard, and another random car will have respawned. Repeat this as many times as desired. You can also easily get the "Proper Scrapper" trophy using this method.
Go to any store, and spend some money. Then, pull out a gun, and rob the store. You will get more money than you would by just robbing the store without spending money. Note: If you are in desperate need of money, do this at a gun store.
Avoid dying near cars: When you are hiding behind a car during a gun battle, do not get near the engine. If the engine is facing the enemy, their gunfire can cause it to explode and kill you.
Playboy magazine locations: Search the indicated locations to find all 50 Playboy magazines: