Mine was sweet itch and still is I recently purchased a 3yo mare this winter and now that the summer is around we have discovered she as sweet itch! But I'm so glad I bought her as she is my absolute heart horse! I would still never buy a horse knowing it has sweet itch
Any injuries, bone changes or any other significant remarks, especially in the legs and back. Obviously it is near impossible to find a horse with completely clean papers, especially it they are a horse in use, and things can always happen, but if it already poses a “threat “ at the vet check to what I want to do with the horse, it’s a no go from me. Other one is the price to training level and/or to health ratio, for example if it’s a more expensive horse and significant changes or remarks are found during the vet check and the sellers are not willing to consider these findings and accommodate them in the price it might very well be left there.
For me, as you probably noticed, healt is a much bigger deal breaker than behavioral issues, as long as they don’t make the horse dangerous, it’s something I can work with if I like the horse otherwise.
Buying a horse, for me if I discover that he has a health problem or a behavior problem, it can be a "deal breaker". That is why it is important to have your trainer opinion and your vet opinion when you buy a horse.
Then when it is about a horse in leasing, I think that as well as checking the health and the behavior, it is important to make sure that you get along with the owner. Indeed, unlike to when you buy the horse, in this case, you won't be the only person taking care of the horse, and the owner's opinion is always the final opinion. So it is always good to make sure that you and the owner have the same vision of equitation. In the world of horses, there are so many ways to understand our sport, that it is always better for an owner and a rider to have the same outlook on things, so that no one will be disappointed in case of problem, and so that there aren't problems about the way to take care of the horse.
Price and condition the horse is in