You could probably get away with an 18ft car hauler with 3500lb axles. BUT, i would suggest 5200lb or 6000lb axles. When I was looking a few years ago, the price seemed to jump when you went to the 7k, but the one posted above seems to be reasonably priced.
Brakes on one axle works fine for me pulling the heavy Bronco with a half ton, but some will insist on both axles. I have heard rumor that brakes on both has caused inconsistent tire wear, but that could be a myth.
Make sure whatever you buy has new trailer tires, and not retreads
Steel deck v. wood deck is a toss up. You could hear arguements for both, but a treated wood deck is going to be a little lighter.
At 80inches wide, you are not going to need to worry about drive over fenders. My trailer is 83" between the fenders and I sqeeze all 86" of Bronco through them.
I would look for a 20' trailer, treated wood deck, dovetail, 2 6lug axles with brakes on one, 2 5/16th bulldog, good beefy tiedowns, LEDS, and new tires with a spare.