First, decide if you'd prefer open or closed. In NC, exposure to the elements shouldn't be a problem. I purchased an open trailer. How much weight will you be pulling? East Texas climate is comparable to yours. If you go open, I suggest heavy duty pipe framing, as opposed to angle iron.
Tandem axel trailers usually come from the factory with only one of the axels braking. I ordered both of them with brakes. (Better to have it and not need it, than to need it and not have it.)
Make sure you get one with enough floor space to accomidate all your equipment. You may choose not to carry everything you have, but on occasion, you might. Same idea as above. Mine is 16 ft long. I have the machine, a 525 gal tank, with enough room in front to carry everything else. (See pics in photo album thread, titled "My new rig".)
By the way, the extra brake axel was only an additional $170.00. I feel it was worth it. Altogether, with TTL, it was $1576.00.
Hope all that helps. you. Take care, and good luck.
Randy