(adsbygoogle = window.adsbygoogle || []).push({}); Pretty straight forward tutorial on how to attack the armoured truck with and get no stars. Requires to have a friend.
This should be at least helpful to lower levels wishing to go legit in GTA Online.

1 . Once an armoured truck appears on the map, have your friend follow it
2 . Head back to your garage and enter and leave. Now the truck shouldn't show up on the map.
3 . Go back to your friend and attack the truck. You shouldn't receive any stars for attacking it.

Enjoy your free money.

Thanks for reading,
Eni.

A easy method; take shotgun, equip silencer and shoot perfectly between the 2 doors. It will take only 2 shots to open the doors. If the truck doesn't move when you shoot at it, you won't recieve any stars.