Where to buy a hall?

where can i buy a guildhall for my guild? and how high are the cost?

You have to go to Lions Arch and board the ship and ask the Captain take you to one of the many islands personally I like Wizard it is a lot like Ascalon in Pre.Then there is guild trader go and price out a sigil it depends on which Island as they are all priced differently.Then get quote on which Island you want and buy a sigil and hand it to the person you got it from or guy.Last time I saw they were going for 60K to 80K there are some who sell sigils if you see them on chat.

thank you very much