It would be best if you could lease a horse first before going out and purchasing one. By leasing a horse you get a feel for horse ownership with out the expense that comes a long with it. Usually the bills are split between the leasers- so you only have to pay a small amount for farrier bills, vet bills, etc. Owning a horse is a HUGE commitment/responsibility and far from "cheap".

Here is a good little article about leasing horses http://www.equisearch.com/novice/guide/leasing061499/