i have a german shepherd, hes 2 years old. hes a good boy good temeperament and is house broken. he knows simple commands such as sit. but when hes playing outside, he wont come to me when i call him. how much would it cost to give him obedience training. i know there are different levels, but i want it to get to the point that if i tell him to lay, hell lay for 5 min without me even being in the room.