I towed an MG Midget 150 miles. I rented a trailer from U-haul. It wasn't a tow dolly, but a trailer. It had brakes. I highly recommend it. It only cost me $59 for the day.

My '01 XE Auto did a fine job towing the 3500 lbs or so. However, there were only a few hills. Most of the trip was flat interstate. Through the mountains you'd definitely want the brakes, and if you're near the 5000 lb limit, you're going to be crawling up hills.
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You can't be a real country unless you have a beer and an airline. It helps if you have some kind of a football team, or some nuclear weapons, but at the very least you need a beer.
--Frank Zappa