Just some more tips from what i've experienced in the past:
The general scam story going around right now is a sob story about how a ladies daughter passed away in an accident, and that she has to get rid of her (insert pet here) because she can't bare to look at it (it reminds her of the daughter).
Essentially they'll go on and on about how they want to make sure that you'll take good care of the animal and you aren't a bad person...yada yada.
They'll write an entire novel of stuff. That's the red flag. No one writes a novel. Legitimate sellers are prompt and direct. They want to sell it for X dollars, at Y day/time, at Z location.
Also, do the following when you find an ad online advertising the sale of Gliders:
#1. Run the photos of the Gliders in google images. It will tell you if they are fakes/copies and where the origin website is. I've almost been fooled by this. I responded to an ad that had images from a UK Glider info website. Of course, I didn't know until I ran the images.
#2. Run their email (if they give it to you/provided on Craigslist). If you google their email address in quotations, it will show you every direct result for the address. You can see if they have a bunch of different ads open, which could tell you if its legitimate or not. One time, I saw a bunch of entries, for a bunch of different pets (dogs/birds/etc). Immediately run from these advertisements,
#3. Run their phone number. This is the same as the email address. But you can also run their area code to see where they are from. I saw some people posting an ad in a state that was different than their area code. Upon inquiry they told me they were out of state and wanted to ship the animal to me. Avoid this at all costs.
Following precaution for buying animals online:
#1. Make sure they come with proper documentation (vet visits/lineage/etc)
#2. MEET IN A PUBLIC PLACE. Can't be stated enough. So many people get robbed, or worse, because they tricked into going to a secluded place. If the seller is unwilling to meet in a public area, cancel the deal. Selling animals is big money for some people. When there is a lot of money involved, the risk for fraud/robbery increases.
#3. Try and get as much info from them as you can. For example, what is their first name(by introducing yourself)? Phone number(texting pictures or communicating)? People unwilling to give general information probably don't want to be known. Avoid them at all costs.
#4. Bring people with you. Safety in numbers, for obvious reasons.
Last little note I can give is, trust your gut.
This is all information i've learned by trying to get MY Gliders via online/through ads. I hope this helps out.