Her canter seems nice to me, straight, and her hind is nicely under her. The first few jumps I wasn't a huge fan of hers, but as she got more into it you start to see her talent for scopier jumps. She just needs to build up her jumping muscles, right now she seems to have more dressage muscles. I see what you mean about extending her canter, but at the end of the video you can see that she can, I just don't think she was being asked for it. For that price, I think you should for sure go and ride her, and see if you click. She's very pretty!