There are an increasing number of boats designed specifically for people with disabilities and most other boats can be made suitable with some modifications. Adaptions can include seats, transfer benches, steering assits and electronics.
Boats designed for disabled sailors
The IFDS Disabled Sailing Manual includes ideas which many disabled sailors will find useful. Simple solutions include the positioning of an additional thwart to assist transfer from side to side during manoeuvres or adding non-slip material to seats.