Check to see if ur unit is autosteer ready, then its just find a reciever and controller and plug and play. If not, trimble ez steer and 250 would be cheapest route. Check the used market, cheaper yet. The 500s have bigger screen. Fm750s are better yet and easier to set up but more expesive and touch screens can get spendy to fix. Fm1000 areCheck with your dealer on cost of mounting kit for your tractor. Need to ask about wiring as well cause it can get expensive. If you know part numbers and have time forums and ebay will be cheaper than new. I like a thumb switch in my FNR levers or gear shift. for engage or disengage vs button on monitor or foot pedal. Usually have to make those from and wire them in to the 25 pin connector on the t2 controller. Ag leader is good but not much support for agleader in Canada. Cnh dealers can help with trimble. I am told deere is good, but IMHO, buy the gps equipment from people who are in the gps business not an equipment manufacturer who sees an opportunity to cash in. I dont see trimble or agleader making equipment. Deere will nickle and dime you. They would rather you buy new than Deere have to upgrade old. Ok if you want to upgrade every 2 years.