The minimum "trib" is
one page, and the maximum is any number of pages you desire to copy and
send. (Fanfic writer-extrodinare Fred Lee Cain is notorious for creating
a second volume of a given issue all by himself on quite a few occasions.)
The only money involved in the publication of the APA is the money individuals spend copying their 'tribs', and the funds they send to the editor to cover mailing costs of the completed issues. And the system seems to be working out fine, since the APA itself has been in existance for over 9 years now. It's an interesting way to share comments and feelings about Takahashi's characters specifically,as well as Anime and Manga in general.
The APA has had members from around the world at various times, so although the name is a typical Takahashian play on words, membership is open to anyone who would care to contribute to the zine.
If you should care to join the APA as a contributing member, please contact the editor concerning the current availabilty of open membership slots... The poor man can only handle mailing out so many copies at at time...