The best 7’ wide enclosed trailer is going to be the one that best meets your needs for hauling cargo and also fits within your budget.
The 7x12 is a great trailer on the smaller size but the extra foot of room over a 6x12 really does make a difference you’ll feel. You can put more in a 7x12 than you’d think, especially when you see the massive 5,000+ pound payload capacity of a 7x12 tandem axle.
Not to be left out, the 7x14s and 7x16s both definitely have their place. The 7x14 is a great middle-of-the-road trailer. Not too big, not too small, this cargo-carrying behemoth easily gets to the jobsite, ATV trails, or live event as a concessions trailer.
Bumping it up a notch to a 7x16 gives you a full two feet of extra length. That’s going to accommodate larger equipment and supply materials with ease. Perhaps it’s a race trailer for a prized show car or motorcycle.