Unseen Butler

You touch the figurine to the interior perimeter of the building you wish to bind the servant to over the course of the casting. This creates the boundaries which the Phantom Assistant will remain in. The total area of the Assistant can be up to 400 square feet, this can be all in one room, or across several rooms.

The Phantom Butler has the same statistics of an Unseen Servant, with the exception that it is bound to a building rather than the caster of the spell and the Butler is partially transparent rather than nearly invisible. The Butler can listen to anyone designated by the caster after the casting.

This spell can be cast once every 24 hours to extend the duration of the Phantom Butler. If the spell is cast in the same building and with the same figurine every day for 1 month, the spell becomes permanent. Each Phantom Butler requires its own unique figurine.

At Higher Levels. When cast with a 4th level spell or higher, the area the Phantom Butler can be bound to increases by 100ft for each level above 3rd.

Taken from u/Bluesamuri33 on reddit.