I think my mini trailer is by "Big Valley". But, I do not know if that company still manufactures. I love mine and it's a stock type trailer but more enclosed than most. It is a 1994 but has been kept under cover and looks much newer than it really is.
I have a wonderful, marvelous, gorgeous trailer by Hart. It has a dressing area that I converted into living quarters, six stalls for horses(can put two more in behind too, ramp to get in) and a big area in the back(with a ramp) for my cart or a mare & foal. I bought it used but just do a search for Hart Trailers. They are in OK but dealers most everywhere. Mine was custom built for Miniatures.
Forgot to say that it has the lift up windows so I can get to them to feed & water without dropping the ramp. And the windows slide open with screens so they can get fresh air. Have I said I love my trailer?
I don't have a mini trailer, don't like them. But my big trailer is really very nice. It's Ponderosa and made quite well. They also have mini size trailers and an 800 # and a website. I do recommened that company highly. They delivered to my door within ten days for $200 bucks.