I think it depends. When I first started buying bags, I didnt' make that much, so my limits were driven by my salary.
Now that I do make more, I don't think I'd spend over $2500 on a purse, unless it was something I loved and had to have.
My thoughts are, if it something that isn't too trendy that I'll love and see as a "timeless classic" in my collection, then its worth the price. Look at it this way, if you buy a $3000 purse but you know you'll keep and love it for 30 years, thats only a $100 a year for the bag.