I am buying an used electric guitar. It is a Fender Stratocaster. What things should i check for so im non getting ripped off? Tell me as much as you can :)

The original price is $100 and I will save about $30 – $40 from buying it online used. I don’t know if they are lying about how much they’ve used it. I looking at both craigslist and ebay to buy it. So what re the Pros/Cons of buying a used amp? Whats your experience with buying a used amp?