Part of Bridgeport's Mystique is that you don't need cars because they have subway stations to get you anywhere you need plus since it's a city everything is close by.
What I do when I want to buy a car is turn on moveobjects and then buy it. Go into live mode and put it in my Sim's inventory then turn moveObjects back off.
To turn moveObjects on and off, pull up the cheat console by hitting Ctrl + Shift + C and a place to type will show up at the top of your screen. Type in "moveObjects on" without the quotations and then hit enter. When you're ready to turn it off, do the same steps but use the word off instead of on.
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