Potion Permit just launched on Steam. In this game, you play a chemist in a town called Moonbury, sick town residents come to you for your healing prowess, particularly by brewing potions.
Check this guide out to know about making more out of selling potions in Potion Permit!
How To Sell Things – Potion Permit
After clearing the early quests of the game and saving the girl, Colin will return and tell you that he has built a mailbox outside of your house.

This will enable you to send back excess potions to the capital for profit.

The mailbox can also be upgraded to unlock more slots.

This is the fastest way to generate income in Potion Permit. However, you have to be careful and make sure you still have enough ingredients to make potions for sick patients when they do arrive.