Here is what they mean by "seeing in game." You can prove that the character exists and under the user's control by:
1) Logging into a DIFFERENT character/account and viewing the character in game, under the control of the user you are doing business with. Have them say a secret word to prove it's them.
2) Logging into the account management page and going to the transfer pages. You can then look up the server and all characters available for transfer, and from there you can prove that the character exists. This will only require username/password and most are willing to provide it.
In regards to your question about the e-mail/first/last name. You can change the e-mail how ever many times you want. However, the first and last name will remain permanently attached to the character. Even if you made an entirely new account to transfer it to, it would require the same first/last name.
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What I suggest:
<ul style="list-style-type: disc">[*]Find another means of contact, especially for the future (phone is a great tool). [*]Don't rush your trade. Do the proper background checks, find any information you can.[*]Make sure you are comfortable with the form of payment you are going to use - if you don't like Western Union, don't use it.[*]Also make sure you are informed on how the form of payment works - be sure to check for guarantees etc.[*]Establish some sort of contract that ensures you are guaranteed from a recall (i.e a refund in the event that it does happen).[*]Most of all, try not to be too nervous about it - it's great that you're cautious, but that may also be a hinderance to those you are dealing with.[/list]
Just be patient and you will find the right person
. Another option is to sell to one of the professional sellers. They may give you a lower price, but it really does save you a heartache in many cases.