I found this a very hard challenge to do, but I also had very limited free time to play, so only did one test run with a couple of things I tried. So I knew I had to get 20,000 to get to a new town, but I hadn't counted on making money to be so hard.
The mistake I made (I think) is not starting in Bridgeport. I started in sunset valley, then moved to moonlight falls and finally to bridgeport. I became a 2-star celebrity in moonlight falls, but in bridgeport I was a 5-star celebrity in no time (just date and woohoo with one of the twee 5-star celebrities and you're done). I only got 3 celebrity gift during my whole challenge, so I might have been a bit unlucky, and all three of them I got when I was a 5-star celebrity. I think know that when I had started in bridgeport, I would have gotten a 5-star celebrity real soon and I had more time to get those gifts. The hardest part (for me) was making money, so getting those gifts (and be able to sell them!) made a big difference. Also the opportunities that you get as a celebrity are a good moneymaker, so if I was to do this challenge again I would start in brigdport to get a high level celebrity quickly.
I fist went to China first, because my Sim got a wish to go there. I used my six days to do some more vacation opportunities to make money (not by selling things, but by completing them). But I still had to make a lot of money before I could move. I only needed to have a date and woohoo a sim in moonlight fall and get 1 promotion (that's why it took my only a couple of days) to be able to move again. I went to France just a few hours after moving to moonlight fall and as I didn't need that much money I just did the things I needed to do. Then I went to bridgeport and maxed the career in the beginning of the second week in that town. I forgot to get my mixology skill started early, so after maxing the careerd I still needed a couple of days to max the mixology skill, while still going to work, and had enough time to make the remaining money needed to buy the car.
I had a lot of fun, but found it really challenging. Congratulations to Nutella on winning this challenge!
Femke82