Here is the full list of all 25 Totally Reliable Delivery Service achievements.
Unlock the rocket booster.
Complete 100 different deliveries.
Bring the conch shell to top of mountain.
Find the big secret bear.
Bring foam hand to Booster Club Arena.
Bring grill to Dad Statue in Golden Ruins.
Bring banana to room 5 at Banana Motel.
Bring the luchador mask to wrestling ring.
Put treasure chest on sloop.
Complete 50 different deliveries.
Unlock the helicopter.
Return the satellite to GASA.
Find the tiny island.
Lose pants in tornado at Happy Clam Resort.
Unlock the pickup truck.
Visit Happy Clam Resort.
Pass gas in a biplane.
Visit Keister Island.
Visit Gasa Research Facility.
Complete 10 different deliveries.
Unlock the buggy.
Unlock the mule.
Remain airborne for 10 seconds.
Complete first delivery.
Change your clothes.