When referring to a cancelled or abandoned mark at the PTO, what is actually being stated is that the registrations for those marks are cancelled or abandoned. The mark may still be in use by the owner and that owner may still have common law rights.
Regarding cancel v. abandonment, the end result is the same - the registration is no longer is active. The difference is typically due to the why the registration is no longer active. Cancellation is usually due to a challenge by a third party whereas abandonment is usually due to some action/inaction on the part of the registrant, such as failure to file a Section 8 affidavit. But, since we are talking about the PTO, there can be some bleed over between these two, such as a record indicating a mark has been canceled due to failure to file a Section 8 affidavit.
If you find a mark has been previously registered but has been abandoned/cancelled, look for why (failure to renew, cancel following TTAB action, etc.). You may be able to use the mark, but you may also find the previous registrant may still be using the mark, and in such a case, you may have to address what rights does that person still hold.
It sounds like you attempting to conduce due diligence on your use. Keep it up.
As for the eBay situation, your response seems to ask good questions. If you have any questions after you get a response, please post them.
I hope this helps.