Why not open auction thread you might get some good offers or bids. Legendary accounts are pretty rare, I think 2+ BTC is fair price. I wouldn't sell mine below 3 BTC.(If i had one lol)
An auction will need some deadline and it will also be binding. I would rather leave it here and let the offers keep coming in. If I get one which I like I will sell.
Not always. You can set a hidden reserve price so that you don't have to sell the account if the highest bid is too low for you.