How to resolve deceptive issue with shady car dealer?

This month, I leased a second vehicle with the same dealer. I am very happy with the car, and I got a great deal; but, I am upset about something. When I was signing the lease, the Finance Manager offered be a maintenance plan for $11 per month that covers all oil changes and maintenance. Based on the amount I drive, I think it would be worth it for me, but I didn't at the time. The day after signing the papers, I called the Finance Manager and said I wanted to add the maintenance plan. He said he would have to redo the paperwork, and the cost would be $21 per month since the $11 promotion from Honda ended at the end of the month. BS! To me, this is completely unacceptable not to honor what was disclosed to me, especially since the never explained that that the offer was limited. Even if Honda does not honor the offer, the dealership should pay the difference ($360 for a repeat customer? Not too much to ask). How can I go about getting them to honor the original offer? The sales person said I will get a survey call from Honda, and that if I give bad grade the dealership will lose its commission. Is that leverage? Otherwise, I am considering calling the Attorney General, the FCC and The Consumer Financial Protection Bureau to report the deceptive practices. I will also tell the story on YELP! Please help.

Read more: How to resolve deceptive issue with shady car dealer?