As a business person (not a breeder but photographer) reputation is very important, in breeding herps even more so. I also get calls out of the blue about how do you do this or that, in my case they are few and far between.

I am sure you are likely get quite a number of questions on a regular basis, to my mind you need to weigh the loss of time and effort in non-customer service against the edge of reputation on the line. I hate not getting answers personally, and often will default to companies whom do answer questions quickly regardless of price difference. (within reason).

My gut tells me that it is likely in your best interest to answer the questions and help out with problems as best you can. It might be worth your time to build 'stock' responses that can be copied and pasted into email bodies that are more generic and sign any non client emails with a foot note about the canned nature and why. Perhaps offering a Paypal link and pay what you can note might work too? When I started I would have been happy to give someone whom would answer my questions directly and with correct information that was tailored to my situation, if you can charge enough to make it worth the bother is yet another question.