You could lease a lightweight wheelchair along with your Motability car.
When you sign up for your Motability car if you want to lease a manual wheelchair along with it let your car dealer know. If you already have a manual wheelchair, but you’d benefit from having a second this might be helpful too. You can find out more information on the Motability website here.
When you order it make sure you specify your weight (products will have a maximum user weight); seat and frame colour choices (if available) and seat size required. And if you want a self-propelling (SP) or attendant controlled (AC) wheelchair.
More info on the G-Logic Chair can be found here.
More info on the Karma Ergo Lite 2 can be found here.