I am not saying I am going to buy one, but could you post some miniature horses for sale here? I am seriously considering buying one.... please post!
PLEASE do not ride your minis!!! They are not built for riding. They are fabulous little horses but driving is what they do. Make sure you do your research on riding minis. You don't want to cause them problems.
Where are you located? I am assuming your would be using it for pony rides or teaching small children. There is nothing wrong with small children riding a mini, which the child ways under 50lbs.
My mini gelding is one broke machine. He rides english or western and bareback with a halter and lead. My younger brother would ride him up and down trails, into the woods, through water, and over small jumps. My gelding is one heck of a mini. He hasn't been ridden in 6 months, and any day I can saddle him up and do pony rides without a problem.
From the AMHA website We discourage all but very small children from riding miniatures. We consider anything more than 20% of the horse's body weight a significant load to pack. AMHA miniatures are not generally considered as riding horses.
From the 20% rule that would be about 30-40lbs on average. You have to figure tack in the equation as well as the child's weight.
I am still suggesting to you that you do not ride your mini. They are not made for riding!