w/craigslist and ebay it depends more upon the seller (and ultimately the item). don't buy stupidly, and you'll be fine
Couldn't have said it better, but you also have to remember, even though the person has 5 stars, or high rep, it doesn't necessarily mean they earned it. They could have bought the account off of someone else.
Don't be too expensive.. and trust your first instinct about the person. :biggrin:
Also, don't be scared to PM the user and ask questions and for photos!