18,250gp in materials, but the real cost is time - you need a high-level spellcaster (at least 9th, if they don't min blowing their one 5th-level slot for the day) to be sat in or around your guildhall every day for a year, without vacations, in order to ensure that they cast the spell once every day.Teleportation Circle - high cost, I think it's around 18,000 gp, but it's a must have.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.