Ah, ok, well, you can see my pics for how long they are and double it ;-) (Consider the jeeps in the pics are 101 and 104" wheelbases, not the 94" of the TJ and YJ)
TJs and YJs are 13ft long each. So 26ft gets you completely on them. You can fit on a 24f if you hang over, I have seen a friend do it this way, it was tight.
My experience is not to *plan* to use every inch of the trailer, if possible. Never know when you need something slightly different on there. Thats why I ditched the 14ft for a 16ft. After I bought my trailer, my dad bought 2 tractors, and they are 15ft long from bucket to rear blade. Like if you go somewhere that your wife stays home but a friend has a truck or cherokee or something...