A few points need to be mentioned over here concerning doing the job properly. The first point is whether or not your domain name is going to act as a sort of trademark over the net because that would demand spending money for the works.
If you are interested in working as so many of your colleagues, dealing with moderating an online auction site, you probably won't need to spend money to register a trademark and reserve your own motto, any useful sentences and phrases illustrating the areas in which your website is operating is going to be fine.