The first car is located in a parking slot in the hills just like shown in the pictures below:

The second car is located closer to the city in a house parking slot:

The motorcycle is located in a parking next to the LifeInvader building:

This car is located really close to the motorcycle in a parking behind a building:

NOTE:
I used someone else's picture I found on google, because the cars don't spawn in these locations after you've collected all of them, at least not regularly.

It's found near an auto workshop:

NOTE:
The second picture is also not mine, because the cars don't spawn in these locations after you've delivered all the cars!

These cars don't spawn at these locations after all the cars have been delivered!

Thanks to youtube user oL0RDo for the provided locations, that I saw in his youtube video and decided to make the guide from!

oL0RDo 's youtube channel: https://www.youtube.com/channel/UCkijvnYl_S6CyFhLDSRFBRw

KIFFLOM