Hi 

I can see you love your dog.

Don't be too worry about the age, he is not too old and many trainers will tell you, that 2 years old dog is perfect for solid work or guard training. As before that he has to react properly and immidiately  for all your basic commands ie: leave, no, wait, watch, sit, come...Also those dogs loves to do a job for people.  Never give up and take a risk, try to trust him as much as u can. I promise, that u will see it was worth of  ur effor..;) 

Enjoy;) xx