If you can afford it, always buy a Trading Post Re-roll
You might find yourself stuck with less-than-optimal weapons and equipment at times because that’s how randomized weapon drops play out sometimes. Luckily, every time you check the store, you’ll be able to buy a re-roll that will give you another set of weapons, recipes, or items. These will be random, but a re-roll is at least a cheap opportunity to give yourself a better shot at surviving the next fight.
