I am considering whether to build a concession trailer out of steel. Here is a commercial example.

http://www.supremeproducts.com/specs16.html

I would make it a frame of steel members and the side panels and roof would also be steel.

Are there any suggestions for a design?

The probable size would be about 8' wide (probably 8' 4'') and about 16 feet long (exclusive of the tongue and hitch) and the box (exclusive of the suspension members) would be about 8' high.

My thinking would be to build a frame for the side panels and roof and weld the plates onto the frame members. I am thinking to space the frame members somewhere between 2' and 4' apart. I am thinking of using either 14 gauge or 16 gauge steel for the plating. I am thinking I would have both outside panels and inside panels, both for the walls and the roof. I am thinking that the frame for the walls and the roof would be 2" square tubing of 14 gauge. What would be most appropriate? I would like it to be somewhat beefy, but I am a bit worried about it being too heavy.

My rough calculations are telling me that the basic box is likely to be well over 3000 pounds.

The base would be made of square tubing. Would 2" 14 gauge square tubing be sturdy enough?

I am thinking that it would probably require tandem axles.

Please give me any good ideas for design and construction that you have.

Thanks.

P.S. Suggestions such as "don't build your own trailer" are also valid.