I was talking sort of about this in another post. I rent u-hauls to do scrapping vacations mainly since if things go wrong I can just get another truck but I like larger ones like 16ft or bigger so I have plenty of space to tear down and drop off at yards as I go along I also rent them for bigger pick ups. I think for everyday stuff if your going to do a lot of weight it would not be worth it unless its something beefy as stated above those small heavy things add up fast. even 10klbs of servers can be a handful of pallets on a big truck and with fuel and other overhead its a pita.
never tried vans and such so no input there but I am sure they are a lot less overhead