I dont have a store nearby, so i do most of my headphone exploring by buying and reselling used headphones. Havent made a profit nor a loss in 20 or so headphones. But in my country (Netherlands) the market is pretty bad, especially with the higher end stuff. People try to sell their (ab)used stuff often for more than new price and get annoyed when you offer them a more realistic price.
VN used market is exceptionally strong, used SA6 here cost like 250$, used B3 200$, used Mest mk2 550$ and so on, all in good condition so good for our community here but Very hard for new brand to compete because of insane p/p value