I have a site I made a couple months ago but I didn't have the money to bring traffic to it. That design is finished although it could be touched up some and it is ready to make money and the domain is about 2 months old but it will need some so work. Could I sell for $100?
That all depends, we need more info. The niche you are in, site name, just basic stuff so we can see what value the site has to a buyer.
Basically you need someone willing to pay that much for a such a site. Contributing factors include having a nice short and pronounceable COM domain, quality content, high PR, or generating revenue already. People are after aged domains or premium domains though, sadly.