TYPED VERSION:
1; Get in your Karin Rebel and take it in to LSC with your friend in it
2; Park it like shown in video
3; Tell your friend to stay in that Rebel
4; Get out and head to your garage
5; Get in the car you want to sell and drive it out
6; Drive it in to LSC and park the car next to the rebel
7; Get out and hold Y (OR TRIANGLE FOR PS3) next to the rebel to push your friend out of the car
8; Get out and sit in the car you want to sell
9; Another personal vehicle will spawn outside
10; Tell your friend to go and get it to drive it far away, then get out of the vehicle
11; Request the rebel from the mechanic list
12; Quickly press right on the d-pad and wait for the loading circle
13; Sell the car for full price
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