Looking for residential care tips for my 21-year old son with cerebral palsy and learning needs

I'm the father of three boys, one of whom has cerebral palsy and is profoundly deaf (he has a twin who's able-bodied and severely deaf). The twins were very premature; 24-weekers in fact. But that was 21 years ago and they're now adults, which is what brings me here, I guess. 

I share care of my son with my ex-wife. As we're both heading towards retirement, we're  starting to think about what happens next, which we've both agreed is some form of residential setting for our son. But finding somewhere suitable - that meets his physical and emotional needs - is proving to be very tricky.

I'm sure I'm not the only one in this situation.

If this sounds familiar to you, do you have any advice or tips that could help, or can you point me somewhere that may be able to do so?

Thanks!