I have done that alot with a 18' trailer. I welded a small short 1" bar to the very back of the trailer. Then I made a T out of tubing that would set down on the 1" bar. Put the first buggy on "try to get in on nose first so the weight is over the axle if possible. Then back the second one on. Tie the back down then jackup the front, I used a $30 farm jack, till it's high enough to put the T in place. Lower the jack and tie down the buggy. The T only needs to be high enough to keep the tires off the ground. I tried lots of differant ways of hauling. This turned out to be the easiest and quickest. Piggy back will work. It just took me so much time to get loaded and tied down. Try this.
