I wasn't sure if the engine and trans would have failed prematurely due to excessive load, although my loads were within the manual specs. I would definately recommend the brakes because obviously stopping is most important, especially in panic situations. With the smaller truck it's a must. Bigger truck, take it or leave it on 3000lbs, but on a mid sized, get them. I could actually stop quicker with the trailer. Also I loved the inersia (sp?) brake controller verses the one in my van now. It will sense a panic stop and apply more brakes if necessary. If they lock up, do a quick pump.
Gas savings was great. not only smaller engine, but less weight. Also shave minutes off trips because acceleration and cornering is zippier.
Also, with my single axel 10' trailer, empty weighs 1200-1300lbs. GVW is 3000 or 3500. I built my shelving with weight consideration. I use 3/8 ply for the shelves with notched 2x2 rails. notching reduced weight and created the lip to keep the bins from sliding out readily. also liquid nailed everything together for rigidity.
To do it over I would consider some of the bed accesories for misc. parts. I'm not a big fan of camper tops on truck beds. an open bed is too convienent when you need it, and besiede, that's what the covered trailer is for. But I do like the idea of the retractable tonnue cover. pricy I'm sure, but really expands your weather flexability. Sometime you might only need the truck, you have to go to the supply house anyway, so you buy everything per the job. They give it to you in a box, your cab is already full of tools and it starts to sprinkle. no problem.
also pay attention to loading. Too much in the front and you'll tax the rear suspension, to much in the rear and the trailer will trail wildly like a broken shopping cart front wheel. keep the weight (wire etc.) in a nonshiftable manner over the axel and then 10-20% heavy toward the front.
