I suggest you also look into installing a new or used “turny” van seat
https://www.braunability.com/us/en/mobility-products/vehicle-seating/turny-evo.htmlas they patient ages and has more challenges you may find that transporting them
“ambulance style” laying down on a EMT style fold flat gurney in the back of the van has advantages.
Extended Chrysler vans with “stow n go” seating adapt well to this.
If there is a car wreck with a frail patient in a wheelchair the outcome is nearly always bad.
If the patient is on Medicare there are many financial options, but many including renting first.
I have 18 years experience and have gotten both male and female patients into vans and all sizes of cars and suv.