Guild Halls guide.
To purchase an amenity, you must use the amenity window, which is accessed from your guild hall's door. Only members of the guild with Trustee can purchase amenities. Many amenities have their own access levels that you can set, to either allow or deny friends and visitors of the hall to use them. All amenities are available for purchase immediately, assuming that your guild hall can accommodate them. The decoration amenities are limited to higher tier guild halls.
When an amenity is purchased, it will appear at a pre-determined location. For most, this is the center of the front room in your hall. They cannot be picked up, but anyone with Friend+ access can move them. To sell back an amenity, you must use the amenity window accessed from your guild hall door. 50% of the purchase price is refunded to the guild hall escrow when selling back amenities. When you sell your guild hall (by purchasing a new hall), amenities will move with you to the new hall, unless that type of hall does not allow them. In such a case, the purchase cost will be refunded to the hall's escrow.
Level 30 guilds start with 5 amenity slots. At levels 35, 45 and 55 you will gain 2 more amenity slots. At levels 40, 50 and 60 you will gain 3 more amenity slots. Starting at guild level 62, you will gain 1 amenity slot every other level. This makes it so that a level 80 guild will have 30 amenity slots. A level 95 guild has 37 amenity slots.
There are five categories of amenities: Decoration, Depot General, Tradeskill and Transportation.
See also: Guild Halls