Just be conservative in your calculations. I tried to get by with a SRW 1 ton because the numbers worked, but I couldn't haul water and I was within 200 lbs of the tire maximum on the truck. I pretty much decided I had to go to the DRW.
Truck tows great, but I sure hate it. Wish now I would have just gone to a Class A and a toad and not went down this path. The truck is a PIA to use as a vehicle once you are there (I like to get back in the woods), PIA to park, and us just a waste as a daily driver if you work downtown. It sits in the garage and only gets taken out when it's going to tow, so to me it's just a 2 piece motorhome.
In retrospect - I was better off personally with the smaller trailer and my short bed SRW 1-ton daily driver.