There are many bugs with this game. Some of the achievements will not unlock even though you do what is necessary to unlock them. I had this problem with this achievement. I found this solution on another website posted by QdogUSMC. I tried it and it worked. Here it is;
1: Start game offline.
2: Load saved game.
3. Enter Eva's garage.
4. After cut scene when your back outside, DON'T get in the car, walk around to the carport (connected to the garage) and pick-up the red spare parts kit.
5. Now get into the car and proceed to drive around the block like she told you. But when you get to the bottom of the hill, stop and get out of the car, there is a pallet of money there, steal it and call in Ewan to pick it up.
6: Now get back in the car finish going around the block and continue around the course like normal.
7. BAM, achievement unlocked.