Do you ever have speciality conversion vans for wheelchairs?

There are companies that convert standard vans to accommidate wheelchairs.  Are any of these ever listed on craig's list? These can be almost any make of car.  They kneel and have a ramp that automatically folds down to let the wheelchairs enter easily.  Some even are able to let the wheelchair replace the front seats of the vehicle with the wheelchair.  Some can hold as many as 4 wheelchairs and still have a bench seat in the back for regular passengers.  They have a safety lock system to lock the wheelchairs down that they don't roll around while on the road.