Of course a vet check should be done, each and every time that you buy a horse..having said that I have never done one, and no one who has bought from me has done one.
When I was considering buying my lease horse, I would have had a VC, because he was far more expensive than anything else that I have bought..in the end I couldn't raise the cash for him, so passed.
The people who did buy him DID do their vet check, even though we knew there was nothing wrong with him. He passed the VC with flying colors, that was in August, and now he has some lameness issues. Only a young horse at 8, maybe nothing, maybe something...you just never know.
“Never attribute to malice that which can be attributed to stupidity”