Among the first things to know about buying a horse is that the horse will need a home. Not everyone can afford a barn, which means that most of us have to pay others to use theirs. Decide how much you can afford to pay a month for your new, very large pet. Decide if you want to take care of the horse yourself, whether you want to take care of your horse some of the time or whether you really can afford to pay someone else take care of your horse all the time. Self-care is generally cheaper than full care.