It's great that your parents are exploring their own options for later, one of the biggest determiners of whether people are satisfied with assisted living is whether they had a voice in the decision. As has already been mentioned assisted living is expensive. With the aging of America this is going to be more and more important for those who cannot afford assisted living. Meals can be delivered, telephone calls daily to check on how you're doing, transportation and adult day care are good services. Your Area Agency on Aging can help you find the services you need.
Many people prefer to stay at home and can with proper support.
But also know that if you need 24 hour help, home care is not necessarily less expensive than assisted living - in fact it may be more expensive, depending on the services that are needed. A geriatric care manager, a professional who specializes in arranging care and finding residential options can be really helpful and save a family a lot of time. Privacy is really important to my mother. Privacy is certainly possible. Many facilities offer private rooms and suites.