Sending convoys to different areas and trading is one of the games key money-making mechanics. For this trophy, you must first reach New York in Sequence 8, and then unlock at least one General Store in New York, Boston and the Frontier before anything else. Then, go to the Accounting Book at the Homestead and open the trading menu. Choose to send a convoy to a store in each area (remember to press to choose different areas) and place an apple in each convoy.
Note - The convoys don’t actually have to reach the cities for the trophy to unlock, as it will do so as soon as you press to confirm the convoy.