i knew shakys history from birth (but didnt know the owner-just very lucky!) and i still got a 5 stage,you can never be sure!!theyve got no proof theres nothing wrong,so your quite entitled to want a vetting,and any friend that tries to disuade u from getting one i'd be questioning their loyalties!!we went to see one and the owner tried every which way to tell us how she didnt agree with vettings and we were still adamant we wanted one, went to see it a second time (before the vetting had been arranged) and it had so clearly been doped/ridden into the ground when we went to view it that my mam got off and walked back she was so nervous (it had barely moved the previous time!)

there could be conformation issues she's not aware of,something underlying that hasnt yet shown symptoms, or it could be that the vet simply says that shes not suitable for the activities you want to do!

at the end of the day its a personal call tho!

Would it make a difference that they seller is a friend (where she is stabled) has owned her since 6 months old and I trust her?  One careful owner and no history of anything? 

There is usually a two stage or five stage vetting. A five stage vetting is the most comprehensive and, IMHO, for a riding horse, the most sensible option. The vet will take bloods at the time of the vetting, perform flexion tests, see the horse lunged, trotted up, and ridden, and give it a general check over for any lumps, bumps, murmurs or crackles that shouldn't be there! x