By far the best value out there is U.S Rider.
They're based out of Lexington, Ky. Great value, and they've already proved
their reliability by rescuing my buddy in Massachusetts. Not only will they tow
your vehicle and trailer, they will also make sure there is housing for your
horses should your trailer be inoperable for some reason. They have great
attitudes and are by far the most horse friendly folks I've had the pleasure of
dealing with. I personally haven't (fingers crossed) had to call on them for
help, but was very impressed with their handling of that particular emergency
situation. I think it was 109$ per year if you and a buddy joined at the same
time. Maybe 125$ if just yourself? I thought that for piece of mind since a lot
of us travel alone that was pretty darn reasonable. 24 hr service 365 days a
year. usrider.org--phone is 800-844-1409. NO--I DON'T WORK FOR THEM OR GET ANY
COMPENSATION!!!! ( i wish).