Audi care cost on lease?

Long story short I overlooked the Audi care calculation when signing the Q5 lease and I declined when finance guy said monthly payment will bump by $30. Next day I realized my mistake after reading a bit and that I could have gotten the Audi care for much cheaper had I asked them to add to selling price and bump the RV by 1% (sigh, thought I had done my homework).

I called the dealership today to explain the situation. They have offered me to sell the Audi care for $648(translates to $18/mo) which is what they said would have been my cost if I had added it with lease after 1% bump in RV. Although when I run the number through calculator the monthly increase is about $12 if Audi care was added in original contract. I wanted to ask here if my calculation is correct?

If your AC for Q5 PHEV is $999, add to selling price and increase RV 1%. New monthly in your case should be ~ $557 all in.

Yep. That’s what I am seeing. It increases monthly by $12 and not $18 which is what dealer is quoting.