I'll to add my two cents. I don't contact a seller unless the money is burning a hole in my pocket and I'm going to buy it as soon as I get a satisfactory response. If I ask a seller a question I give them 24 hrs to respond and then I and my money move elsewhere. I have found that nobody is selling anything I can't find somewhere else.
I probably have past up buying good stuff from good people, but many a seller has past up selling their stuff to me by treating me like a bother. Some have told me they don't always respond because they get tired of people asking questions or making requests for more pictures, when they aren't going to buy anything. These things may be true, but that's not my propblem, and I'm the one risking $$$, not the seller who won't even ship until he is paid.
Sorry if this is a rant, but it's a sore subject with me.
Marc