Leslie's idea is good, but I think some IT people have cars like that, too. I have seen one of Indy's vehicles; wasn't that a Lexus van you drove at Tahoe?
I think you could ask for either an NPI or office phone. Both are public information and could be obtained or faked with a little work by a determined individual. Both could be verified on Bert's end in a couple of minutes.
But I think the average "spammer" trying to get on here will not go to the effort to produce either. In other words, ask for an NPI or an office phone number, and don't bother to check either one unless you later decide there is a need in specific cases.
