"Elderly and vulnerable - caution!"

My 90 year old house-bound mother (who lives alone) had an at-home eye test and was prescribed two pairs of expensive glasses, one being polaroid. She has dementia although appears confident and assured. I think the optician should ask vulnerable people if someone could be present. The fact that my mum's (limited) bank card payment was declined, so he accepted a cheque from an old cheque book should have rung alarm bells. Fortunately Outside Clinic agreed to refund the £360 second unnecessary pair.