Dealers are just expensive. At least yours recommended the valve adjust. Mine didn't. With no warranty to worry about, I'd find a good independent Honda Mechanic. Valve adjustment is not something to skip. Honda valves tighten up and this makes no noise and can cost you a valve job or head if they get too tight. I did mine around 175k and one exhaust valve was tight, others close. I did plugs at the same time, they are in there and have access. Sorry but I don't remember the cost but it was not over $500 a couple of yrs ago.