Morrowind:Zainsubani Informant

Quick Walkthrough
# Return to Caius in Balmora for your orders.
# Meet with Hassour Zainsubani in the Ald Skar Inn in Ald'ruhn.
# Visit the nearby bookseller, Codus Callonus, and buy a book as a gift for Hassour.
# Give the gift to Hassour and receive the note for Caius in return.
# Return to Caius in Balmora.

Detailed Walkthrough
Orders from Caius
Caius Cosades' next task is to try to establish an Ashlander informant. He has heard rumors that Hassour Zainsubani, an Ashlander who is now a wealthy trader, is staying in Ald'ruhn. Caius gives you 100 gold and asks you to try and find out what he likes and buy him a present in the hopes of persuading him to talk about the Ashlanders tribes and their relationship to the Nerevarine Cult. Although Caius says he's not sure where to find this gentleman, he suggests the Ald Skar Inn. If you haven't been to Ald'ruhn before, it's basically far north of Balmora, past Caldera. The quickest way is to grab a Silt Strider from Balmora, although Mages Guild members might prefer to use the Guild Guide instead.

Meet with Hassour Zainsubani
The Ald Skar Inn is just southwest of the big Manor District building in Ald'ruhn and Hassour is on the middle level (there are stairs right of the bar leading to the area). First thing to do when you talk with Hassour Zainsubani is ask about business and that will bring up the topic about gifts. Chatting with him you indeed find out that it is an Ashlander custom to give gifts and that Hassour's passion happens to include poetry. So, just give him that book of poetry you've been reading and... what, you don't have one? Well, time to visit the local bookshops to see what books they have in stock. Note that you can also talk to other people to get this info, or explore his room in the other, larger downstairs part of the Inn to see what sort of books he has. Just as luck would have it, Codus Callonus' bookstore is located nearby, and Codus actually suggests a few selections when you mention Hassour (Words of the Wind 45 gold, Ashland Hymns 35 gold, or The Five Far Stars 25 gold). Now, if you have explored Hassour's room, you'll know he already has all three of them but he'll accept any as a gift. If you're really tricky (and cheap) you can steal one of his own books from his room and give it back to him (he shouldn't notice). Alternatively, if you raise his disposition to 80 or higher, you can discuss the Ashlander gift-giving customs, and he will take your "thought and effort" as a gift.

Return to Caius
Once you get Hassour to talk with you about the Ashlanders and Nerevarine Cult, you'll receive his notes for Caius. Return to Caius, and he again promotes you and suggests you keep the notes, as he is sending you to the Urshilaku Ashlander Camp that Hassour mentioned. He also goes on to explain things a bit. It appears that you were released and recruited on the Emperor's orders.  The Emperor believes that you may fit the Nerevarine prophecies. Caius gives you a decoded copy of the original package you delivered to him along with 200 gold and instructions to see Somutis Vunnis and Crulius Pontanian at the Moonmoth Legion Fort before heading up to see the heads of the Nerevarine Cult at the Urshilaku Camp.

Notes
It is somewhat interesting to note that Hassour is in the Thieves Guild, meaning it will be easier to persuade him if you are also in the guild, but more difficult if you are a member of any of the Great Houses or the Temple.

Hassour's disposition is set to 70 when you hand him a book, not raised by 70. If you press him for information without having given him a book, his disposition drops by ten.

With Hassour's disposition at 80 or higher, simply asking after the gift-giving customs of the Ashlanders will satisfy Hassour, and he will respond that your thoughtfulness of attempting to locate a gift for him is enough to make him happy.  He will then freely provide the information necessary for the quest, and the act of buying a gift is skipped.

Hassour also offers you a quest if you talk with him about "life as a trader".

Bugs
 
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Quest Stages