Bargaining is normal practice for first hand items. Just do it the right way.
If you want to claim that the item is cheaper at another store, please buy there instead.
I help run retail, and I get this a lot
For second hand though, please, bargain before you actually meet the person to deal.
If you want to claim that the item is cheaper at another store, please buy there instead.
I help run retail, and I get this a lot

For second hand though, please, bargain before you actually meet the person to deal.