Not just any public land will do, if you want to DIY then and have really good chances its going to be tough. You need to be in a good unit, pre-scouted, etc. Its hard to DIY if you aren't able to get extra time off in advance to figure out the unit your hunting, see if their are trophy bulls in the area, etc. Plus many of the really good units can take years to get into. You need to know the terrain, elk movements/locations, etc in advance or your hunting time is really going to increase and your chances lower. Spending 10k on a hunt will give you much better chances and make it much more likely to succeed. Unless your a resident of the state your hunting its hard to get pre-scouting in, etc. A hunting outfitter isn't going to have you shoot a small bull as it reflects badly on them. No one wants to book with an outfitter that is shooting babies, people book with those consistently shooting monsters. My top choice for an Elk hunt would be Colorado.