This post is basically for the new-to-towing crowd but the veterans might get something from it as well.
The tongue weight seemed high on my trailer so I checked it this past weekend. Basically, the idea is to have about 10% of the loaded trailer weight, on the tongue. Too little tongue weight results in a trailer that sways when pulled. This can be unnerving at best, and very dangerous at worst - search youtube to see examples.
My 24 ft enclosed trailer weighs about 6,800 pounds (although I’m planning to confirm it on a local truck stop scales) loaded so my target tongue weight is about 680 pounds.
Using four jackstands and wood, I was able to quarter the tongue weight and use a bathroom scale. On the first check, it read 273 pounds! I have a weight distributing hitch (look that up if you’re not familiar with it) but almost 1100 pounds total tongue weight is too much, even for a full-size Sequoia.
I removed the 20-gal compressor, generator, and a set of tires from the front of the trailer and got the tongue weight down to just over 800 pounds, which is within the factory rated tongue weight for the Sequoia. The car is already positioned backward in the trailer and is strapped-down at the rear. The tailgate door almost touches the front bumper. When I used an open trailer, a strip of duct tape beside a front tire, on the trailer deck made it easy to position the car in the same spot every trip.
Relocating some items in my trailer will help but just knowing what I have, helps for sure. And regardless of the trailer you use - open or enclosed - this method is a cheap and quick way to get an idea about the tongue weigh of your trailer.