I love Gypsy Vanners and so I found this online for you guys, it states GV are not a small breed only and can come in any size. Mini, classic, and grand, however, the average size is 14-15hh. CHeck it out:
" There are three different registry classifications for the breed, based on height. If the horse is under 14 hands (56 inches, 142 cm), it is considered to be a "mini Gypsy". If the horse is 14-15.2 hands high, it is known as a "classic Gypsy", and if the breed is 15.2 or taller, it is known as a "grand Gypsy". In 2004, the breed became recognized by the United States Dressage Federation All Breeds Program, and can win breed-specific awards whenever it wins a dressage event or any event sponsored by the USDF."
Sources for the info above:
Mountain View Vanner Ranch - HISTORY OF THE GYPSY HORSE Horse
Gypsy Vanner Horse Breed | Gypsy MVP