What features to look for when buying a tow dolly?

We expect to buy our first motorhome soon. Since none of our current vehicles appear to be towable four-down without a lot of fuss, I'm seriously considering getting a dolly to tow our 2011 Accord with the front (drive) wheels up. That seems a more sensible option than trading it only in order to get something towable without a dolly.

I know very little about dollies. I never before looked into them much. I thought that either my little sports car or my pickup truck would be towable four-down. So, where to start in shopping for dollies?

My question: What features should I be looking for in a tow dolly in order to make life with a dolly on the road and around the campsite more tolerable for an old man? Please name the features that you looked for, or wish you had looked for, and tell a little about why they are important to you.

Thanks!

Wayne