Making sales pages for only 3%?

I am currently looking for a way to make money online that will help me get a new car relatively soon. I was thinking about making a sales page for people who are selling cars, boats, and motorcycles on Ebay. I've looked on the website and have seen post that don't have a sales page, no interior pictures and/or have a horrible description. I was thinking of charging 3% of their sales price and requesting 10% of the 3% up front. I already have a preview made. Does this sounds like a good plan to make enough money for me to buy a car? I have HTML, Photoshop, and copy writing skills. Thank you