I'm with Nenugal on this one.
Unfortunately, to my experience, not everybody takes care of their teaware as well as I do. With the exception of trusted TeaChatters, I would want to be able to at least take a very good look at the teaware in person and also at the person selling the teaware, I suppose
It also depends on what you are buying. If I was looking for a plain white porcelain cup for instance, this is something that is hard to take bad care of and even if the person had neglected to keep it clean, it could be restored to "like new" status rather easily.
Started the TeaDay with Okuyutaka sencha this morning. Then had some coffee, actually. I can see Kaoru Supreme Organic Matcha sometime in the next couple of hours (I really like that one, best out of three that I've tried from O-Cha!), then maybe some Yutaka Midori Sencha and possibly some houjicha or genmaicha in the evening.
My thoughts and hopes are with the people of Japan with every sip.