Doug, your Christmas tree trailer pic is funny.
I have one just AFTER Christmas. Here's the accumulation of years worth of unused decorations, on top of my weekly trash run to the dumpsters:
Steve, you should be fine with a BOB. I have less than $80 bucks in my single wheel trailer and usually end up with 45-60 pounds of groceries in it once a week. Look on "crazyguy" and do a journal search term for trailer and you will find quite a few pics.
The single wheel can't be loaded like a double wheeler with the weight balanced leaving little weight on the skewer. I've played around with heavy stuff and a scale. Although all of the weight is suspended between the rear bike and trailer wheels THERE IS more weight placed on the trailer wheel if it's placed in the back of the trailer. Side to side balance is far more important.