An update to
Rocket League later this month will bring Rare and Very Rare items as well as a trade-in system to the game. The new items are only obtainable through online matches and include “themed items inspired by our “meta” theme to be revealed later this week (it’s a surprise, you’ll love it), rare decals for cars, and some very rare new Boost trails,” according to Psyonix. Meanwhile, the new trade-in system will let players exchange five items of a particular rarity level for a single item of the next-highest level.
Furthermore, a second update following the one later this month will add player-to-player trading.
“Some items, like those with “Painted” or “Certified” attributes, may become much more valuable if you can trade them to other players. The “Trade-In System” is designed to let you get rid of unwanted or duplicate items, but you should consider carefully what you trade now versus what you might want to keep for future player-trading opportunities.” — Psyonix