"Why do so many sellers take offense to offers on their listings?"
How are you making your offer, is it binding through the Audiogon system or is it a weak-ass, noncommittal PM where it means nothing? I can handle low ball offers and respond in kind. I have nearly 300 transactions on A’gon and have been here 20+ yrs (in spite of my profile saying 11-yrs). What I do here is purely hobby related, in my professional life I sell for a living and know what pre-qualifying a buyer is all about. If you contact a seller through PM you are def relegated to tire kicker status (i.e. time waster). I can’t tell you how many times someone said "ill buy it at X price" through PM and not follow through. The PM function is for asking questions, not making offers to buy.