i don't get it. I never said people can't sell accounts if they aren't the original owners.
In that case, @James should then recover the account (I think the seller should try prior to @James, though). @James would only really attempt it if the seller can't recover it.
In the event that neither can recover, that I'm unsure about. It would have to depend on the reason. If it's locked, maybe the seller would have to refund partial, if not all? If the account is recovered then James or the second seller would have to pay up.
Now, in the event that someone is selling an account that they aren't the original owner of, they are fully responsible of everything. They will be considered the original owner and have all the responsibilities that go along with it.
I'm not sure about this, but I believe that after 6-12 months of uninterrupted use of an account that the current owner would then be a full owner, therefore he should be able to recover it with ease, depending on how actively that person played RS.
In the event that the original owner has quit the site, the seller may or may not be fully responsible, it all depends on the situation, though, to be honest.