As we stated above, obey they law. But there are creative ways to keep inside the law. If an individual can't buy and sell more than five cars per year, perhaps your spouse could buy and sell some after you hit your limit. Some articles suggest googling for your phone number before calling. If your number shows up with lots of used cars for sale, these websites will tell people to stay away. Perhaps you can periodically get a new Google Voice number and set it to forward to your existing phone. It's free and relatively easy. It really shouldn't matter if you've bought or sold cars before, but some people are funny that way.