There are so many car duplication methods in GTA 5 and it is hard to find the simplest method of them all. As such, we have done an extensive research on the best method around and discovered the following.
There is one particular glitch where you are able to sell the duped vehicle for a full price. Fully modded street cars can go all the way up to $10K and super cars can go at its full price. However, some users who’ve tried this experienced a $50K limit message. To get over this, players can just keep doing it with the Rebel.
To exploit the glitch, you can follow the guide below.
1) If you encounter the $50K limit message, start off with a rebel instead. Get inside your car in the garage and wait for the name to disappear.
2) The moment it fades, spam the Triangle and R2 (Y and RT) button quickly and repeatedly in that sequence. Do make sure that the Triangle button is untap when pressing R2.
3) If done correctly, the camera zoom will change or the car door will open slightly.
4) You will then spawn on foot by your car. This car is a duplicate. Simply drive it to the nearest LSC to sell it. While driving along the way, call your mechanic to deliver the car you are in. If you have that $50K issue, request for the Rebel.
5) Now, retrieve and reinsure the original car.
6) To do it again, leave the game session and join in a new invite-only session. Then, repeat all of the steps above. For the Rebel, simply blow up the car and start with a new Rebel straight away without leaving the game.
This is the best and fastest way to make big money in GTA Online. You should make full use of it while it is still around. Otherwise, you can stick to grinding by repeating the same missions again and again which leads you to nowhere.