Please be aware that depending on negotiations and reasons you provide, it is highly probable that any sale will also involve a public announcement that the account has been sold for all to see.
Please detail your offer and reason - do not ask for my price. Price + just reason will get you the account.
Now that's just silly. Nobody is going to buy your account if you do that. People will want the account for signature campaigns but you have no control over what they will do with it in the future. If you're uncomfortable with selling your account privately I suggest you just don't sell it at all.