You should be changing transmission fluid every 60,000 miles max (although I like to go more aggressive at every 40,000-50,000 miles) - drain and fill with fluid change (including filter change, if applicable).  Have you gone to an independent mechanic who works on Japanese vehicles to get a quote?  Out of warranty, I would avoid the dealer at all costs - they are called stealerships for a reason.  You can also do yourself if you are mechanically inclined, understand how things work, and feel comfortable.

https://m.youtube.com/watch?v=eRxSu4-4ojo

probably because it doesnt have the trans dipstick

getting ready to get my kids done at 75000, i get the feeling that you should change coolant and transmission fluid every 60,000 miles, from the comments on here