Once you have unlocked the expeditions (completed the story) you will be able to buy rares/legendary items from Tiago for Drop Pod Resources (DPR). There is an easier way to get what you want instead of just grinding expeditions over and over again (you can also do this while grinding expeditions).
How to Get Legendary Items (from Tiago)
How It Works
- Break down gear that has a mod you haven't acquired yet (if you want/care).
- Mark all items in your inventory you do not plan to use with the colored boxes in the bottom right.
- Sell all to Bailey for Scrap.
- Use Scrap to buy Titanium from Bailey.
- Trade Titanium to Tiago for two DPR each.
It's that easy.
This isn't some crazy secret, but it can be easy to overlook. In just a couple hours of playtime I had enough scrap to convert into Titanium/DPR to afford 2 pieces of Tiago's "Elite offers" (Make sure your World Tier is high enough to equip them).