What is the most profitable vehicle to steal in gta v story mode?

The provided Wikipedia evidence discusses Grand Theft Auto Online, which is a distinct online multiplayer mode separate from GTA V's story mode. Story mode features a different structure with specific missions, characters, and vehicle interactions compared to the online component. The evidence does not contain information about vehicle theft mechanics, profitability calculations, or stealable vehicles within the story campaign. Additionally, the concept of 'profitability' from stealing vehicles doesn't apply to story mode in the same way as online mode, since story mode focuses on narrative progression rather than economic systems. Without verified evidence specifically addressing story mode vehicle mechanics, I cannot provide an accurate answer about the most profitable vehicle to steal.