My wife is in late-stage Alzheimers, totally incontinent, and unable to speak sensibly. Ideally, I would like someone who would do the things for her I am doing now. Daily personal care, daily soiled laundry, feeding (she is a reluctant eater), and light housekeeping in the rooms she occupies. Am I expecting too much?
If your wife is a fall risk, you need someone who knows how to assist someone who is unsteady. You need someone who knows how to be patient and creatively get your wife to do beneficial things. Also be clear about "phone breaks" so they aren't looking at their phones every 5 minutes.
Make sure you have a written contract. Is this person going to be privately hired? Or through an agency?