Medkits and Lockpicks are lifesavers. Imagine being stuck in a room with low health and zombies attacking you? Exactly. For these sorts of scenarios, you should always have medkits and lockpicks in your inventory. You can find medkits in ambulances as well. You’ll also find lockpicks or you can just make them with metal. You can also buy these items at vendors if you have enough cash to spare.