What is the average dealer mark up?

50 %.....

I will echo a previous poster, it’s important to get the terminology correct. Audio dealers have:

100%+ mark-up (% of the cost of goods they inflate to form their selling price)
which equates to 50%+ gross margin (% of revenue left after cost of goods)

Those are typical numbers on hardware, accessories and "tweaks" you are in the territory of 300% to 500% markup easily. To the dealer that isn’t doing well despite 75% gross margin, you are grossly mismanaging your costs and your business.

My challenge with B&M dealers is that they are not offering the value they are supposed to. Most of the dealers I’ve visited are not knowledgable, at times I knew more about their product and their competition than they did. They would praise every piece in the store without an honest assessment of their weaknesses or my needs. It feels like they are steering me to whatever brand/piece they want to sell at the moment. In fact I had two different dealers wire speakers out of phase just so they could boast about how big the "soundstage" was.

This to me is not all that complicated.  While I realize it may be part of someone’s nature, or they grew up in a place where bartering is the accepted norm, I find having boutique dealers in this consumer segment to be essential.  I think many of the commentators on this thread probably have some measure of business acumen and understand the economics of being in this hobby (for lack of a better word).  The commenter who was complaining about letting the cat out of the bag for dealer margins is not considering that a.) humans can’t keep secrets, ever and b.) so what?

I expect to receive knowledgeable advice, and I don’t mean like basic info, I mean real help in guiding me toward the next inevitable upgrade.

i fine paying a premium for this.  If you just can’t help yourself from going into the bazaar mode, wait for sales and buy online.