Outside of a trainer (which I cannot help you with, sorry) I would say that some of his "acting up" is because he's bored and doesn't get enough exercise.
The cost (in CDN $ is about $130 for 90 minutes) is a decent price LOL I've been quoted anywhere from $100 - $200 depending on "what" I was looking for - behavioural / training, etc.
I agree with the "one good correction is worth a thousand bad ones" ... especially at his age. Unfortunately, I also agree that you did drop the ball on this, and it will be much harder to correct now (always easier to teach the "right" thing, than to correct the "bad" thing).
I noticed you indicated that you have an appointment in January .. is there ANY way you can get an earlier appointment? I can just picture how much more frustrated you and your dog will be to wait two more months ... I know I would be climbing the walls!!!!
Marion’s Zoo-Kyleigh, Raylan-cat, Echo-TAG,