National Company
Uncommon24.7%ObjectiveOptionalAnywhere
Own a garage in every city in your headquarter country
This can be done in any country - but the easiest (cheesiest?) way to do this is to establish your company in Luxembourg; as there's only one city so the achievement will pop immediately!
Otherwise you'll need to buy more garages where you wouldn't necessarily want to, and at 180k apiece that will take longer into the game to be affordable.
For your first three garages you'll have to drive to them and into the green euro symbol floating marker. After you own three, you'll then be able to buy more from the map menus without having to actually travel to them.