Beach Hopper Achievement
Race in 50 Multiplayer events on Long Beach.
You need to complete 50 events in multiplayer on a Long Beach track. This can be done in private matches with a single Drivatar. While any mode where you can select the Long Beach track works, I suggest a Timed Race on the Long Beach Full Circuit set to 30 seconds. If you want to race against a lower class of car, select a C or D class car and go to the lobby screen. Then press to go into the settings and change the car class to Any along with any other settings you did not set previously. Press to accept your settings, then again to go back into the menu where you can then select any vehicle you wish to ensure an easy victory. Note however that you do not need to win, you just need to complete the match. This means you can start the race and sit there for 30 seconds if you wish. If you choose a modern Indy car, this will contribute towards the "Long Beach Veteran" achievement as well.
On the Xbox One Achievement App, the tracker across the bottom of the grey achievement picture can be used to track your relative progress.