We dipped our toes at FW this past fall (cabin rental). We have thought about renting an RV via a preferred vendor, but I can honestly say that the golf cart is a must when seeing the Christmas/Holiday lights. I seem to recall that some of the RV renters do provide a golf cart rather than going through a dedicated golf cart company.
What was really fun is having a dead car battery and getting AAA approved to enter FW for service; it all worked out and was thankful they (Disney) had vetted the AAA driver/vehicle before entry.