I live in Arizona and need a wheel chair van for appointments. Any ideas?

Does anyone who lives in the Phoenix area have a wheel chair accessible van that I could borrow from time to time to take my mom to medical appointments? I have been paying upwards of $120.00 each time I take her to a doctor's appointments. We need to be able to take her for bloodwork, etc. Dial a Ride doesn't go out of our particular area.