More to the point:
Tire Kicker (typical definition)
someone who appears to be interested in buying something and asks a lot of questions but does not buy anything: If you want to sell it on the internet, you'll have to deal with hundreds of tire kickers. (So true)
For me, I don't mind answering a few (few) questions, but not continuously. A buyer should have some item what it is they are attempting to purchase and understand its function (you would think). If you need a complete technical description of the item, its capabilities, accessories, options, etc., can you not do some of that yourself before you consider contacting a Seller? Most ops do know and asked the pertinent questions (i.e. lowest price, payment instructions, where to send the item, perhaps an additional pic or two (if a website only provides for one), and that is all acceptable.
I think the best solution is like one poster stated. Whomever gets the payment to you the quickest, is the buyer. If someone gets left out in the cold being too non proactive, then too bad, so sad. I don't like to do that but perhaps that is the best approach.