It's a great idea. We all know that the need for assistance as we get older is growing and growing. There is not going to be enough assistance for my generation (Boomer!). You will need to keep your eye on the changes in reimbursement and adjust your plans as needed.
I might suggest that you follow closely some of these facilities, maybe even volunteer/shadow the owners/administrators in order to get a good idea of their day-to-day challenges. In many states, you may also need to obtain an administrators license of sorts.