How can i figure out how much my registration will be!! On a 98 Lincoln navigator

Registration and title fees are same for class c vehicles and then you pay MA sales tax on vehicle depending on how much you paid for it. I paid $135 total in fees relating to title and registration and service (not including taxes) . Not sure if it'd be same but probably.

I paid 400$ for the car

I don't know what the registration fee is on it, but I think the registration fee is the same on all class c vehicles