I'm not sure exactly when I know someone is a tire ticker, but it's usually pretty far into the process. I've pulled up to houses and thought, "No way I'm getting this job". And 3 weeks later we are painting the house.
I know I'm going to deal with a certain number of tire kickers/ price shoppers. Oh well. If I try to get too cute so I can eliminate all of them, I'm also going to eliminate some potentially good customers.
We don't try to do any pre-qualifying. If they will meet with me, live in my service area, and want something I do, I'll be there.
This may come as a bit of a surprise, but I have a lot of confidence in what I offer, as well as my sales skills. When I show up to look at a job, my attitude is that they will want to hire me, but wonder if they can afford me. After all, who could resist my boyish smile and that little twinkle in my eye? Actually, a lot of people can, but that's beside the point.
Seriously, I think it's a mistake to try to prequalify or weed out tire kickers. Often the customer simply doesn't know what they want or need, and if we spend some time with him/ her we can open their eyes to other possibilities.