Assuming is a terrible thing.... sorry.... however based upon what I have read so far....
*** If you want your hunt to be
enjoyable and hunt focused, 
thenhike inand hunt on foot with back up arrangements made to have someone pack outany elkyou kill.
*** If you want your hunt to be
memorable and filled with some off-the-wall experiences, 
then go ahead and get the horses and have at it; however, it may be more of an epic and less of a hunt. No better way for some one to get hurt than to screw around with horses, especially if you are not "on your game" OR if the horses are knot heads. Nothing worse than a bunch of broncs.
Sombrero Ranch rents horses in Northern Colorado.After the first elk season was over, a hunter showed up at their ranch headquarters witha pickup and horse trailer to return his rental horse "in person" rather than let one of the Sombrero "hands" pick the horse up at his elk camp (as they will do, good service really). The foreman approached the hunter and they exchanged greetings and salutations and then the hunter in a very business like fashion inquired of the foreman as toconfirm the horse rental contract language that stated that if the horse died for any reason while in the hunters carethat the hunter had to pay $1000 for the dead horse (back then, it is more now). The foreman confirmed that $1000 was the fee and inquired if a horse had died. "No, just checking," said the hunter. The foreman indicated that the hunter couldpull the trailerover to the horse corral and he would recieve the horse and sign off on the paperwork.
The foreman walked toward the corral. The hunter walked back to his pickup, grabbed his rifle, opened the endgate, the horse stepped out, and the hunter shot it dead right there. The foreman rushed up in disbelief and anger. The hunter then handed the foreman a check that he hadfilled out in advanceand told him it was the most satisfying money he had ever spent and that he now considered the score even.
Rental horses can be a real crap shoot, especially if the owner doesn't know you and hasn't had experience with you and your treatment of his stock. If it is your first year, then you can't really expect to get his best stock. Lord only knows what had happened out on that hunt to cause that hunter to shoot that horse. Horses can make your huntor ruinyour hunt. Your call. If you go with horses, then a packing school would be superb, however, most folks won't take that step.