Pics will help answer your question about whether you will make money. Lots of people know girls they think are "hot" but if you want advice from experts then post some pics so they can decide and offer you useful input.
"she just turned 18" is not the only magical phrase you need to sell a solo girl. "Hot" and "sellable" are too completely different things, even though they can be related.
There are many other factors that come into play:
What is her personality like?
What type of content will she do (nn, softcore, hardcore, fetish)?
Will she do cam shows?
Will she stay in it for the long haul?
What is she willing to do to promote the site? Will she go to shows? Do interviews? Appear on TV?
More information is needed beyond "I have an 18 year old girl who is willing to take pictures with me," to make any assessments.
