Congrats on making the smart decision to dolly tow and save the wear and tear on the driveline of your Avalon, plus saving the high cost of mount plates, tow bar, lighting system, and brakes to get just 1 car ready to tow.
The Eze-tow is rated at towing a car of 4,985 curb weight and with the widest track - 80".
Car Tow Dolly -The Lightest and Toughest Tow Dolly For All Car Towing Needs - Acme Car Tow Dolly Company
You will have to check each mfgt for the weight rating of each of thier dolly's.
But, don't believe anyone who says you need a swivel pan or steering axle...with the steering unlocked on the toad, the front wheels will pivot to make any turn, then re-center - Eze-Cheezie.
I have over 10,000 miles on my Eze-tow dolly and I bought it second hand...so simple and Eze to use.
The other brands are all heavier and cost more, but the dolly doesn't have to be heavy or expensive to work well.
Best of luck