A second garage will be available soon. Get all three, one in each gang color.
Silver, yellow, green, purple soft top Tornados
Purple, green, yellow, blue hardtop tornados
That's 8 cars
Yellow, green, purple Mananas
Maroon, purple, green, yellow peyotes
That's 15 cars if you want every gang colour in those three cars.
Then you can do
Green, yellow/black, green/black, purple/cream Buccaneers. For a total of 19 Gang cars and there maybe one or two I haven't had.