One thought. If you buy used do it from a very respected dealer or a private person sale. You want the trailer that was a 2 week vacation guy used but a few times. the thing you don't want is my trailer. My trailers are used 7 months of the year and hauled all over the US. Mine are more than used even though they are well taken care of.
I always by new because I am going to use them to the nines, same way with my trucks. I look forward every few years for totally new stuff, old people like new toys.