Just doing a quick google (
Health Screening) it seems that the average UK hip score for labradoodles is 12 (with mum’s being 11 that sounds average).
Labradoodles have all the issues Labs might have, so they’ll want scores for hip dysplasia, elbow dysplasia and progressive retinal atrophy (PRA). Apparently poodles also have issues with Von Willebrands disease (a blood disorder), Addison’s disease (a pituitary disorder) and allergies/skin problems, so worth asking about that too - i.e. any history in the family.
@Leanne ’s points on number of litters and ‘aftercare’ are really good too. Also ask about inbreeding - they should have a coefficient of inbreeding (CoI) score which basically shows how inbred they may be, apparently 8% is usual for labradoodles. Good luck to them, hope it’s a positive visit!