it will be good experience in any case - just to see how a business can be run. I myself am starting my own online business - but at the moment im doing research into the market to see if its feasible (so far so good), and then I have to do a lot of running around to check which importers will be willing to do business with me - and that means i have to set up relevant documentation proving to them that there is a market for the products that i wish to sell.
Its nothing to do with cars btw
So yeah, i say go for it. You learn a fair bit, you make a bit of money and you may even have something that could be a main business instead of a side business. I suppose you already know the target areas so you can work on advertising etc. But as i said, its a learning curve, so just have fun and see how far you can go with it.