Hi the answer depends on hat style modis it is the older ones use the personality keys , when you get the update they include any new keys so if two years ago an update came with new keys then you got them and if last year you got another update then you would get that years keys if needed but not prior year keys so if you didnt update each time you would get the newest software which will include everything from start to finish , however any keys that came out on years you didnt update wont be in the latest update. That being said you may not ever need the keys that you dont have and they are available sepeatly . If you are looking to buy a Modis I would recommend a modis ultra there are no keys needed it is much much faster almost no time to start up and use and the update is only software and a new update will get you everything you need . Sometimes our snap on guy offers a discount program where you buy an update and get the next one free however if you dont update everytime i think there is a cost for multiple prior updates .