Here is the full list of all 40 Roundabout achievements.
Complete your first eSports Speedrun Challenge.
Reach a 35x multiplier.
Drove straight for Beth.
Collect every star in every ride.
Honk your horn 500 times, then honk your horn 500 more.
In "Death from Above", survive for 30 seconds.
Purchase a pet eagle.
Die 360 times.
Reach 100% completion on a mission.
In "Destruction Derby", take out 8 cars.
Stand still for a minute of silence at The Memorial.
Aggressively warn a dozen pedestrians with the Trafffic Coner.
Unlocked the Traffic Coner.
Unlocked the Pickup Finder.
Make a huge mistake.
Unlocked the Inflatiboat For Cars.
Unlocked the Reverser Wheel.
Purchase something from The Chrome Dome.
Purchase some property.
Follow a lady into the big smoke.
In "Ball Bouncers", bounce the ball at least 12 times.
Collect every star in a single ride.
View the "How's Your Driving" screen outside of the DMV ride. Useful, isn't it?
Unlocked the Multiplier Freezer.
Unlocked the Beary Nice Music Box.
Survive the Mountain Fair Demolition Derby without exploding.
Revolve over 53,596 times.
Get a better eSports Speedrun Time than the No Goblin team.
In "Run Like Crazy", get 150 yards away.
In "Limocide", take out 50 pedestrians.
In "Farming Simulator 1977", complete your farming in under 40 seconds.
In "The Great Hunt", find 6 regions.
Collect every Cash Stash.
Accomplish every Sick Jump.
Discover all of the horns.
Purchase every hat and paint job.
Purchase every property.
Reach 100% completion for the entire game.
Complete an eSports Speedrun without exploding.
Drive the entire "classic" length of Desert Limo without crashing.