GTA Online's Bottom Dollar Bounties DLC added several new missions and vehicles to the game. One such mission that has caught the attention of players is Dispatch Work, where you play as a cop and take down criminals and get paid for it. Here's a guide on how to get started and complete police dispatch missions.
How to Start the New POLICE Dispatch Work Missions! | GTA Online Vigilante Guide
In order to access Dispatch Work and do police dispatch missions in GTA 5, you will first need to purchase a compatible police vehicle. To get one, grab your phone, open the internet and go to the Warstock Cache & Carry website (see image). On this page, you can purchase any police car that says "Dispatch Work available" so that you can do the new mission.
Currently, only six police vehicles support Dispatch Work in GTA Online. I've listed them all with their prices and unlock criteria in the table below.
The list above gives you an idea of the requirements to unlock these police cars. Most of them require you to complete some sort of quest from the previous DLCs, which can be time-consuming for new players. The Unmarked Cruiser seems to be the best option though, as it’s the cheapest and has a fairly simple unlock criteria. You just need to survive for five minutes against a Wanted Level of 3 stars or higher in GTA Online to gain access to this car, after which you can permanently add it to your collection for $3,950,000.