If the vehicle is fitted with a parking camera, it is not required for the car to be fitted with parking sensors also.
It’s important to note that Motability will not directly pay for any car to be fitted with these devices; it is a pre-agreed pricing arrangement with the manufacturer. For example, all Ford vehicles will have rear parking sensors if sold to a Motability customer.
If the car does not have them fitted as a factory standard (so let’s say a Ford Fiesta that is at the dealership with no sensors), the dealer is expected to retrofit them for you or order a car with rear sensors. Nothing more, nothing less.
Should you need anything else, such as an optional extra or adaptation for medical reasons, and you are unable to afford to do so, you could ask Motability for a one-off grant.
Bottom line: if there’s a camera, there is no requirement for parking sensors also. If you want to check this or ask for support, call Customer Services on 0300 456 4566.