The submarine - becomes available after Sonar Collections Dock (250k) is purrchased
The tractor - unique, rusty old-timer. It is located noext to the house near thelighthouse.
The military base - Fort Zancudo is a limitless source of military equipment. You can find there the tank,P-996 Lazer jet and choppers, among others. Watch out, however, because each instance of breaking into the fort results in a four-start pursuit. The tank goes out of the fort on patrols so, you can wait for it right outside of the gate (this does not raise the alarm if you do not cross the barrier) and attempt seizing it when it is close. When it comes to jets and choppers, you should look for them in the runway.
Nagasaki Blazer - an unique ATV. After you complete the game, you will receive a message from Ron, while playing as Trevor. He will inform you that he left a present for you next to the trailer. Visit your Savehouse to claim the ATV.
Space Docker - An alien car. This is where you meet Omega and start the quest of collecting the 50 parts of the alien spaceship. After you have collected all of the parts and given them back to Omega, you will watch a cutscene, in which you enter the garage. The car is in the garage and you can take it after the cutscene ends.
FIB SUV and Buffalo - in the region of the huge satellite dishes, you start a little event. You will find there the FIB Buffalo and the FIB SUV. Stealing them will not result in any stars, but the nearby agents will react to this and start fire. If you wait for a moment, they will start a quarrel after they meet up and will start firing at each other.
HVY Dump - Huge dump trucks used by the nearby workers. A non-operating one can be found on the elevation.
Park Ranger - A vehicle of forest rangers. You can find it behind the gate of the array complex.
Addler - Several tens of meters to the south of the nearby clothes store. You can find it parked right at the Addlers street. The car which you would purchase for the "mere" one million dollars!
The Buzzard chopper - A military chopper. Much easier to obtain than in Fort zacundo. It is on the rooftop of the government building. You do not receive a star for intruding. All of the doors will also be automatically opened, once you approach them. To ma it onto the rooftop, you need to take the ladder at the back of the building.
Lifeguard, Vapid SandKing - A lifeguards' vehicle. At the same beach, directly to the left of the fun fair, you can also find the Vapid SandKing XL off-truck.
Los Santos Airport - The airport is another location where you can obtain airplanes. Here, you can find Luxor and Shamal, among others, and purchasing these would cost you as much as 3 million dollars. You need to remember that, if you do not own a hangar at the airport, entering will result in receiving three stars.