Los Santos Customs Upgrades A Single Car, or the Entire Brand?

[maddogrussia]

Hello,

As Franklin, I just bought Los Santos Customs.  I think it was money well-spent.  For $375,000, I get free upgrades.

Of course, I used the "COMET" cheat, and then decked it out with all top-notch upgrades, etc. that were probably worth $100,000.

My question is:
 

1.  Every time I spawn COMETS, steal cars, etc. will these upgrades carry over?  Or, will I need to go to Los Santos Customs and upgrade every time?

I break so many cars, spawn new ones, etc.
 

2.  Should I need to get new upgrades each new car, what to do?

Should I just save choice cars at a garage, and use those sparingly?

3.  Any way to sell those upgraded cars for extra money?

[Phelps_1247]

1. No you need to upgrade them every time. Its self explanatory.

2. That up to your choice.

3. No. You can't sell cars in SP.