You have to get a "Perfect!" score on every car (except Xzibit's) to earn this achievement. The basic strategy is to make sure you find the secret supplier in the cash roam phase, bring lots of cash, and get every Xzibit special upgrade. To maximize your cash, start out by collecting all of the billboards and meters, then get all of the cash tokens and complete all of the cruising events. When the only dots left on your map are the two green ones (music events), start crashing into things until you get to within $100 of the target. At that point, go complete the two music events, redoing them as necessary until you get the max score on each. This should give roughly twice the minimum cash. As soon as you do the first one, the timer starts counting down for pimping out the car, so make sure you do as much damage as possible in those two minutes while still completing both events.
Next, in the pimping phase, move through the map in a logical order, making sure to get to Xzibit in a hurry when he announces a special challenge or if you see a special parts supplier (red star on map). You can restart the pimp phase without repeating the cash roam phase in case you need to change your order of attack. Also, each Xzibit challenge gives you extra time on the clock if you get there quickly, so that is an extra incentive to get there quick!
At each supplier, order the highest star value item available. If you are short on time, press ASAP to pay full price and add maximum time to the clock.
If you have problems finding the suppliers in the cash roam phase, here is a list of their locations:
Marcia – In the same parking lot as the southwest blue cash token.
Andrea - On the north eastern side of the waterfront drive, just south of the tunnel, on the east side of the street.
Hari – From the southern music event, go west. The supplier is on the left before the first turn.
Leon - In the container yard south of the starting position delineated by the two triangle intersections, towards to northeast corner. You have to drive through the piles of containers (i.e., not on the marked road) to find him.
Alix - directly north of the southernmost music event on the dead end road the goes southeast.
Aiyana - in the west section of the map, when you exit the tunnel turn north and follow the road. It will turn southwest, then a sharp turn to the south-southeast. After you pass the two white roads on the right, the supplier is just past the turn to the east, on the north side of the road.
Jason - East of the starting position is a cruising event, with a white token north east from there. The hidden supplier is on the opposite side of the street from the token.
Sandra - 1.5 blocks west of the northwest cruise event at the top of the map.
Zeke - At the northernmost tip of the map, east of the blue cash token.
Na - One block west of the southern music event, on the west side of the road running north-south.
Jewels - From the eastern cruise event, exit to the east and go south until the road ends. Turn left and the supplier is on the left.
Vinny - On the road to the north section of the map, right when you exit the tunnel the supplier is on the right.
Chadborn - At the intersection west of the northern music event.
Satomi - In the lower section one block north of the blue cash token.
Lucas - In the lower section, go east from the music event toward the blue cash token. About 1/3 of the way on the left, just before an auto supply store.