This client's son is working towards getting his drivers license. Currently someone else will put his walker in the car and take it out again when they have reached their destination. However once he is able to go out by himself there won't be someone else to help load and unload the walker. He is able to walk to the back of the car and fold the walker but would need help with bringing it in and out of the trunk. He has this walker model:
Crocodile Adult Reverse Walker - Size 3 | Pediatric Gait Trainers 

Your task is to design a system capable of lifting a walker in and lowering it out of a trunk of a car. It must not damage the vehicle and should be weatherproof. It must also be easy to use independently and easy to maintain. Ideally it would be adjustable to any vehicle and any walker to be as universal as possible.