Going and getting a project bike is a big deal. It's the first step! But you want to know what you are getting yourself into. Not every used motorcycle seller is as honest as your dear old grandma, and you want to scope out exactly what the bike is going to need so you can start planning a budget and plan of attack for when you get home.
When you get there TAKE. YOUR. TIME. It's not worth rushing yourself and possibly overlooking something big and expensive which will need replacement. Don't let some pushy kid rush you. If you get a bad vibe, back off. This is your motorcycle here we are talking about so lets do it right, and check out every single angle of the bike before we leap into a financial decision.
Here is a 3-part series on how to assess a new motorcycle:
Once you get through it all, you should have a basic idea of what you are looking at. Remember too to also utilize any additional resources that you may need. Pretty much every motorcycle out there has an online forum dedicated to it, if not several. Google it and ask the hundreds of owners what common problems their bikes face. Tell them about your potential bike and see if they think its a fair price.
Finally, people send me links to craigslist ads and such ALL THE TIME to see what I think. I'll be happy to give you my opinion, just use the contact form on the home page. I am a real live person!