There are laws against owning certain animals within city limits or in other areas. Find out if they pertain to your area and apply to the animals that interest you. I also think herd animals are happiest with a same-species buddy. I've seen so many people buy colts, refuse to geld them or train them properly, and end up terrified of a stallion who is spoiled rotten and totally out of control once his hormones kick in. All of that heartache could have been avoided with a bit of common sense and responsible buying.
All breeders produce the good, the bad, and the ugly.
If you don't know the difference, don't expect the breeder to tell you, many won't. Do your homework and get some experience before you try to leap into the breeding arena. You may find the reality isn't what you fantasized at all. These things may seem like a lot of trouble and wasted time, but I guarantee you'll be in a much better position to enjoy your animal or animals if you are willing to buy responsibly. You'll know what to expect and you'll be prepared even when an emergency occurs.