100%

yes i think you can, i have never tried this but i am sure that you can complete the game 100% with cheats as well, i have never completed this game 100% without cheats i think i will try and complete it with the cheats. :)

U should try trainers Ucan Spawn cars and other vehicles unlimited health unlimited ammo no reload and many many other things u should see or for faster complete download a Savegame File

You won't get 100% game complete if you have used cheats and saved the game. However if u haven't saved the game after using cheats then you can get it to 100% normally. Its well known with GTA gamers and modders community so you can check it yourself on all official GTA forums. Thats the beauty of this game you have to play without cheats to have 100% game completion. Its fun, addictive and quite easy so you can get through without using cheats, infact it will make missions look much more interesting. So try playing missions without cheats you will love it as usual.