I always had blueticks and they were an amazing dog. Hunted around and with people that had both of the reds. Both were good, even tempered dogs. The redbone might be a little bit more calm around a family. Was always going to get a redbone but got sidetracked with other things in life.
My uncle raised Redbones for years and had his own blood line. Used them for Coon, Bobcat and Coyote and were even great family dogs. Unfortunately we don't run them much anymore due to my aunt being a travel nurse and my uncle is always on the road with her so he got rid of most of his dogs. Red Bones are very mild tempered if you work with them, but you put them on a track and they will not leave it, just what you want in a good hunting dog. $100 dollars is a bargain for a good hunting dog, if you're serious about getting one I would jump on that deal.
$100 bill is cheap if it's from decent stock. If the dog is friendly and looks good it's cheap anyway.