When it comes to knowing how to sell art, many artists are pretty good at it. To survive, either they or someone in their organization needs to have mastered the basic techniques of selling art.
When working with artists, one thing I have found that applies in nearly every case is they don’t make big offers. They tend to get shy or sell based on what their own budget looks like. It is a serious mistake to make offers to a prospective buyer with a mentality of not much in your own wallet.
Art buyers are sophisticated, but that doesn’t mean they know exactly what they need. Further, they often don’t have enough information, or good suggestions, to be the best informed buyer. If you can help them by making bigger offers than they might have imagined on their own, some will actually be grateful and accept you offer with no haggling.