I have an 2004 Interstate West 16' x 7' ramp door with the millenium package (ATP stone guard on front, ATP on tongue, spare tire, inside lights, roof vent, outside loading lights, RV style side door, 4 floor d-rings and 4 wall d-rings, rear stabilizer jacks, torsion spring axles with brakes on both, with sales tax and CA DMV fees it was about $4500.
My friend bought, from the same dealer, a 2004 Interstate West 20' x 102" Car Hauler (4 ft longer, 18" wider, larger side door, and finished ceiling with two roof vents...no ATP, no spare, no rear loading lights or d-rings in the walls. Hers was about $5200. Quite a bit more trailer for only $700 more, but it was more than my tow vehicle could haul comfortably.
Interstate West is middle of the road price/quality.
I also looked at PACE, Haulmark, Featherlite, TPD, Carson and AZ-Tek.
The Featherlite and TPD were much more.
The PACE and Haulmark were a little more expensive. Even at the same price I would have bought the Interstate. I liked the interior finish more in one, and the exterior more in the other. I didn't dislike either on the Interstate.
The Carson Racer model was about the same price and I felt, much poorer quality.
The AZ-Tek was considerably cheaper both in price and quality.
I towed with an open trailer for close to 15 years, never understanding why someone would spend 'so much' on a trailer and not put it in the car or seat time. Now I know. 1--storing the race car in the trailer versus inside the garage frees up garage space=happy wife who can now park her car in the garage instead of in the driveway means less hassle on money going towards the race car. 2--Keeping all of your stuff in the trailer saves so much time packing and unpacking. Less stress when trying to load up and get on the road. Quicker to put the trailer away and get a shower, go to bed after a long weekend. 3--You won't have stuff blow out of the trailer, or be exposed to the weather. 4--When at the track you have a place to get out of the weather. 5--You are less likely to forget something if you never take it out of the trailer to begin with.
Drawbacks--you MUST resist the temptation to leave the car in the trailer until a week before the next race.
You MUST be pretty confident that it and all your belongings are pretty safe where it is stored.
They are harder on your tow vehicle.
I don't know why it took me so long to do it...yes I do, I am a tighta$$. The only way I'd ever go back to an open trailer was if I went rally racing...I don't want a service crew dragging an enclosed trailer to some of the places they might need to.
While I am on my soapbox, feeling like anyone gives a rats' a$$ about what I am saying, get a truck and use the change for an enclosed trailer.