Are any discounts or special offers available?

Tokai Kisen Discount Information
https://www.tokaikisen.co.jp/boarding/discount/Shinshin Kisen Discount Information
https://shinshin-kisen.jp/service/Izu Shoto Kaihatsu Discount Information
https://www.izu-syotou.jp/price/Ogasawara Kaiun Discount Information
https://www.ogasawarakaiun.co.jp/service/New Central Airservice Discount Information
https://central-air.co.jp/schedule-fee.htmlANA Discount Information
https://www.ana.co.jp/ja/jp/guide/plan/fare/domestic/ichiran/Toho Air Service Discount Information
https://tohoair-tal.jp/ext/fare.html