Found out recently that permanent trailer tags are available in NC.
Waited for my two to come due and purchased both this week...$75 each, but will last as long as I own the trailers...what a sweet deal! Annual tags were $15, then went up to $19 either this year or last year, can't remember....but anyway, well worth the money, since I plan to keep more than 4 more years!
How about your state? Is this an option? Do you take advantage?