Rather than tacking onto an existing and long topic, I'll start fresh. See here for more mods like this. I own a Barker 15 Gallon Folding Tent Trailer Tote-Along. Despite my best and repeated efforts to get the others in my party to conserve water and reduce their usage, we produce a fair amount of gray water. I'm slowly being able to make it through a standard weekend without having to dump it until we pull out. But, they are who they are and I love them anyway. Obviously, the last place I want to carry it is inside the PUP. DW said "no way" and this time, I have to agree with her. The first place I tried attaching it was to the spare tire on the rear bumper. Great idea and pretty easy and fast "on and off" except that it interfered with EVERY time I wanted to raise or lower the roof on the pop-up. That lasted about two trips. Next, I lashed it to underneath the tongue of the PUP beneath the LP tanks with several cam straps. This worked but was slow, especially when trying to work the dump station on pull-out day. I'm trying to be courteous and fast. This lasted a few more trips. You can see it in the lower left corner of this picture. When looking for a solution, I stumbled upon a rear, under-mounted carrier by Coleman for one of their PUPs 10 years prior to my current model. It was for this very model of tote. It was OEMed from Barker, so I tried contacting them with a Barker part number, etc. No response. So I made one. I have no idea if I've infringed on designs because I didn't pay much attention to the details of that one, just the idea. I know several folks on here have mounted their totes underneath their TTs, 5ers and the like, but I don't recall one being under a PUP. Probably because PUPs have no clearance underneath them. I had done an axle over/under conversion last month, so that opened up this possibility. I used 2" angle aluminum stock (3/16" thickness) for the frame and some flat bar for making cross bar supports. Here it is during mock-up. Duct tape holds it together and the milk crate approximates the height of the rear when mounted. And lining up the tote for a dry fit before committing the drilling and fastening. Here is the carcass fully assembled. At this point there are only 34 rivets in use. I've never done any metal work so I have no idea if I made it appropriately, over-built, under-built or just plain wrong. During mock-up, the wheels did not want to roll over the 2" tall edge, so I made ramps from more of the angle stock and change the 90 degree bend to more like 60 degrees. Those are the tabs along the bottom edge. Here it is, straight on, as if you were looking at it from behind the camper. To mount it under the PUP, I needed it to drop down when I remove the pins at the rear bumper so I used two L brackets, each with a T hinge attached to give me the proper height and a pivot point. The angle brackets are attached to the metal whiffle tree cover and do not interfere with the operation, and only minimally with servicing tasks. These are the only bolts in the entire design, so that I can remove the carrier as needed. I did not want to drill into the OSB type flooring as 1) screws might come through to the isle inside the PUP and 2) I don't want a thin layer of wood supporting the weight and forces that will be exerted during travel. Here is a little closer view of the mounting brackets. Here is a close-up of the ramp and part of the hasp. Here is a close-up of the latches made from hasps and carabiners. It makes for a very fast process. Unlatch the carabiner, drop the carrier and roll off the tote. Reverse the process and I am gone. This is a view of the finished product. It turned out well, I think. It took way more time than it should have, but it was a learning experience for me. And that is a good thing. Note: I did not design nor desire for the carrier to support the tote with anything in it. That would be too much weight in the wrong place, and I don't think it would support nearly 150 pounds.