For the first 5 years we owned our motorhome, we did a combination of renting at our destination, uber, and u-haul dollies. All worked and had their uses. The u-haul route worked well for us on longer trips to a single destination, cause we'd do two one way trips dropping off and picking up the dolly close to our destination so we didn't have to store it at camp.
Ultimately this year we set up our Ford Fusion Energi to flat tow. It's fine, but something we already own and use as a daily driver. If I were to pick something specifically for flat towing, it would sit higher off the ground, and be a simpler/lighter vehicle. CRV or Wrangler probably.
It cost me around $1500 to set up our car to flat tow (and that was buying most stuff used). That's a lot of renting/ubering. But it's also SO convenient having the car with us and being able to hook up/disconnect in a few minutes.