I have bought three horses online. One from Oregon, big 17.2hh Saddlebred that I sold when my granddaughter needed a kidney transplant. Second was a Clydesdale out of Florida, my son and granddaughter rode her. She spent 5 years with us before her untimely death. She is buried in my son's yard :) Third was a an APHA buckskin who spent too many years as a broodmare to want to be a riding horse again. She came to us from Illinois. So she was sold and back to being a broodmare.
All were ok purchases. Horses were as described for the most part. Buckskin mare didn't have as much riding time as was stated and would rear when asked to leave the property. Other horses were excellent and Vickie the Clydesdale was exceptional!