(a) A trailer that is eight and one-half feet or less in width and of any length and that is used for commercial or business purposes.
(b) A trailer that is used temporarily on a construction site for office purposes only.
(c) A mobile modular unit.
(2) "Special use trailer" does not include any travel trailer. [1985 c.16 §26; 1993 c.696 §7; 2003 c.655 §90a]