If the button color is Green, you are allowed to bid on the vehicle.
Yellow color means that the bidding is about to close, you need to hurry up.
Gray color means that the bidding is over, you cannot bid any longer.
"Run & Drive" stamp means that the vehicle starts and is able to move on it's own.
"Engine Starts" means that the vehicle starts but does NOT drive.
"Non-Drivable" means that the vehicle does not start and does not drive.