Selling parts

In want ad's I usually look for a location on a signature . If I don't see it I usually don't answer. Maybe others will see this and get the drift if they need parts show an address. . I have tons of parts but will no longer send out of the US do to past problems with shipping costs. The quote is always a lot lower then the actual charges. ???. I have many parts left here but I found some of my parts selling for more then I charged the buyer. So I answer want adds as I see fit. Sorry but this is only caused by other members looking to make money on others. This just happened with a gas cap sold it for $30 locally and saw it resell for $100. I also get several missing parts that I know were secured in the package. This always seems to only be when they go to foreigners. Steve