I just picked up an adult male with a 55 gallon tank, rocks, food and water dishes, wood, UTH and some calcium dust for $0. Turns out the son had lost interest in the beardie and the mom just wanted him gone to a good home. Heck, she even delivered him to my house, that's about 30 miles away and well over an hour drive. So, yes, there are people that are either in over their heads or just can't continue to care for a beardie that will let them go for next to nothing.
Actually, I rescued my first beardie and pretty much got the same deal that I mentioned above for him.
I will mention this; neither of my rescues had UVB lights and one of them has stunted growth. Ask a lot of questions:
Approximate age of dragon?
What lights are you using? How old are they?
What are you feeding? How often?
Are you dusting with calcium and multi-vitamin? How often?
Has the beardie been to the vet? Checked parasites?
How often has it been handled? Any handling problems?
Check the enclosure for a recent poop? How does it look?
Look at the location and judge the temperature if a thermometer is not present
Hope that helps,
-Jim