from my experience, mostly peddling of long term benefit followed by attempted guilt trip and then really missing your chance here bs. you can either debate them on real merit of total cost or bs them with excuses or tell them not really interested and you just wanted the reduced rate for a cheap weekend..then you get the stink eye look.
or you and spouse can play good cop, bad cop and you can blame her if she is good with that. just have her pull you aside a couple of times during the discussion and then they will take the run at her.
each salesman can get creative though, imagine your teenage daughter trying to get her first phone....that is a dream I am living right now....no means no....what part of no do you not understand...double stink eye look