The issue of portability has a couple of factors worth discussing. First of all, what sort of vehicle will you be hauling it with? Secondly, how close to to the place where the bench is to be used can you drive? I started out transporting my bench, disassembled, in the bed of my truck, a small Toyota PU with a shell. I would assemble and disassemble it every time that I used it. That was fine, if a little time consuming. I leaned the inverted top against the tailgate and either screwed the legs on or off. Finally the light came on and I realized that I could simply leave the legs on and slide it into the bed. (My truck's bed has a rubber mat.) The camper shell is tall enough for the legs to clear. (The bench is 34" tall.) Now, when I need to use it, I load it into the truck, drive to where I will be shooting, slide it out "walk" it into position balancing it on the front corners of the top, rocking it from side to side, advancing one corner and then another, controlling and balancing it using the legs as handles. The result is that I do not have to lift or carry it. When I have it where I want it I flip it over so that it rests on its legs, and then adjust the fourth leg so that the table does not rock. To load it, I reverse the process. My point is that the weight is not an issue because I have learned how to handle it by balancing the bench. I guess the time that I spent working for a moving company while I was in college was not wasted.
Years ago, I built a bench that was able to be transported in the same manner as my current one. The frame was not designed to be taken apart. It was made of 3" square steel tubing, the top was laminated, three layers of 3/4" ply(back then it actually measured 3/4") Since the steel was free (column drops) and there were some heavy nuts and food long pieces of allthread laying around, I made each of the legs adjustable over a wide range. Since the allthread was over an inch in diameter, the bench rested directly on its ends. Adjustment was done with a good sized Crescent wrench which was used to loosen and tighten large jam nuts. We moved is the same way as I do my current bench, flipping it into the truck bed, back out at the destination. I described it as semi portable. It was very rigid because the legs were welded to a frame of the same material rather than being individually attached to the top. I could load and unload it by myself.
