No response from sellers??

Always ask questions before buying even if you think you know the answer just to help establish the credibility of the seller if not already known.

Ads only run for so long. No excuses for not answering questions during that time. If questions do not get answered to your satisfaction, punt and move on.

"Try leaving your phone number"

Bad advice. Use the provided mechanism for submitting and tracking questions. If it does not work, let audiogon know. If a solution is not offered stop using audiogon until you can have faith in the system.

Never ever publish or otherwise disclose personal info to others unless you trust them. Does not sound like that is the case in this instance.