Trailers in shipping are two different things.
A trailer can be anything from a small flatbed trailer with one axle. These are typically used to haul something small like a lawnmower, golf cart or something else. This kind of trailer can be pulled by a small car.
On the other end of this scale are the massive trailers used to haul giant equipment and the big enclosed trailers pulled behind a semi-truck. In either case, a big vehicle or something with plenty of pulling power is needed to move these trailers. Of course, trains pull big trailers as well.
Trailers can be enclosed or open. For instance, hFor orses are shipped in enclosed trailers. Cars can be shipped in an enclosed trailer or an open trailer. Two-level open trailers are used to haul many cars at once, usually from a port or manufacturing plant to a car dealer.
Some people also call shipping containers a trailer. That is not exactly correct since a trailer is supposed to have at least one axle and wheels. Shipping containers have neither. A shipping container is placed on a special flatbed trailer and then pulled by a semi.
California Transporter is the company to call when you need California Hauling trailers either for one move or repeated moves.