Long ago, I used to hang out in Kazham a lot because there were all kinds of opportunies to make money, and as a white mage, you need to be creative in that department.
One of the things I used to do was to make a trip to Jeuno and buy one or two Protectra II scrolls from the shop in Lower Jeuno. When I got back to Kazham, I'd sell them for about a thousand gil higher than what I paid for it (it worked out to about 8,000 gil, if I remember correctly) at the auction house there.
White mages, who were leveling in Kazham at level 27, would gladly buy the scroll for the slightly higher price rather than make the trip to Jeuno themselves.
Another scroll you could try getting your hands on is the Stoneskin scroll. Stoneskin is only sold in the town that is currently winning Conquest, and only to citizens of the country that's winning. In other words, if Sandy is winning Conquest, only San D'Orians can buy the Stoneskin scroll and only from the magic shop in Sandy.
So...
If you happen to have a mule who is in the town that's winning Conquest that week... you could have it buy the scroll, and send it to you in Kazham so you can sell it at the auction house there. Since it's level 28, white mages will be in Kahzam about the time they would be interested in buying it.
I believe the Stoneskin scroll sells in the NPC shop for about 8,000 gil. I'd sell it in Kazham for about 10,000 gil.
The other money making approach I used to do was to sell produce. If you walk down the dock next to one where the airship lands, you can speak with mithra running the airship shop without paying for an airship ticket. That mithra sells all sorts of useful produce, especially Kazham Pineapples, Kazham Peppers, and Mithran Tomatoes.
You could buy a few stacks of these and put them up for sale on the nearby Auction House which is tied to Windurst... where the Culinary Guild is

So, if Windurst didn't control the Elshimo Islands, the cheapest place for people to buy these cooking materials without leaving town would be the auction hourse
On Alexander, people did this with the pineapples and peppers alot, but few did so with Mithran Tomatoes. So I usally stuck with selling 2 Protectra II scrolls, 2 Stoneskin scrolls, and 3 stacks of Mithran Tomatoes on the auction house at all times. I didn't become super rich, but it was enough to live comfortably off of until I could start mining Yughott Grotto and Gusgen Mines in safety.