Walden, a game

There is controversy surrounding this achievement as to whether you must have $100 all at once, or you simply need to acquire $100 cumulatively throughout your game. Some players have it pop after acquiring $100 cumulatively, and others only when they have $100 on them. As a precaution, I would not spend ANY money until you have gotten this achievement. This will lock you out of some achievements for the time being as some require you to spend money. Some ways to earn money include: Harvesting your bean plants when your food storage is full, repairing Emerson's house, chopping wood in the forest, collecting Young Waldo's toys around Emerson's house (cannot be done after you complete the Good Friend achievement), collecting specimens for Dr. Agassiz, completing surveying jobs, and turning in manuscripts for Greeley. I suggest while you are going through the game, make sure to keep your bean plants in check as they give you a hefty 21 cents per plant when your food storage is full. You can earn a large amount of the money by completing all the jobs in Concord mentioned above, if not all. If you don't have all the money, the best way in my opinion is repairing Emerson's house, as there is a fire right inside so you can recover from your exhaustion quickly. You can earn about 45 to 51 cents if you start at fully rested. This achievement popped for me at around the $101.50 mark.