You can increase durability on both weapons and armor by equipping the right perk cards - I don't remember off the top of my name what they're called, but there's one each for weapons, armor, and power armor. At Max perk card level, they double the item's durability when you repair it.
In other words if an item has a base durability of 50, if you put the perk on the next time you repair it, it will double the durability to 100. You'll see the extra durability as a brighter line superimposed on the original durability line.
It's well worth building those up, although I don't suggest having them equipped when you're out exploring the world- better to switch builds and use them only when you're repairing.
when you find armor pieces, the durability condition is related to your points in luck iirc
I’m almost positive it’s random sadly, the mods you have equipped on them also affect the durability.
What about legendary drops? I'm looking for a T-51b set and I'd like it to be in its best conditions
You can increase durability on both weapons and armor by equipping the right perk cards - I don't remember off the top of my name what they're called, but there's one each for weapons, armor, and power armor. At Max perk card level, they double the item's durability when you repair it. In other words if an item has a base durability of 50, if you put the perk on the next time you repair it, it will double the durability to 100. You'll see the extra durability as a brighter line superimposed on the original durability line. It's well worth building those up, although I don't suggest having them equipped when you're out exploring the world- better to switch builds and use them only when you're repairing.
Gear you pick up is dependent on luck stat as to how high it's durability is, craft d gear is dependent on intelligence