I own a landscaping service in PA. I have used them all! Here is what I found:
i am down to a TRITON aluminum 6x12- awesome trailer but it does have a price on it because it is top notch quality and all aluminum.
I have a Pace American enclosed- I looked at 12 different brands of enclosed trailers before I bought this one. They all use the same .030 thickness aluminum siding except for Haulmark (i think) which is only .028. They all have the same axles (Dexter) The price differences is ridiculous between brands.
The axles can be either leaf springs or torsion bars. Torsion bars are more expensive, need maintanace, and do nothing! I put thousands of miles on these trailers every year with very heavy payloads on them. I dont remove my equipment during the season so the trailers are always loaded for 9 months. You will NOT notice any difference with the torsion bars suspension, at least I cant.
The best Bang for the buck, PACE, hands down. If you got a Haulmark for the price you said, sounds like a good deal. my Pace 6x12 was $2400 in 2000 at Home Depot! They will give huge discounts if the trailer is damaged in any way, so look one over and get the manager. Hope this helps