It's shameful how dismissive they are when asked to back a belief with scriptures.
Of course their immediate thought is to refer house-holders to literature on JW.0RG
Back in the day everyone I went in service with, except for newbies or children, could maintain a good discussion going an use their memory or the Bible words and Topics referenced on the back of the Bible, (my fave was the bright green "Make sure of all things" book, though).
If a house-holder had time we'd discuss for over an hour or even more, and if they were folks in the car, no big deal, it was easy time, and you could take a nap, then head to the coffee shop for a bathroom break and a snack.