This cave is right outside of town, near the silt strider.

Be sure to use F to ready weapon If it's a bow be sure to drag the arrows onto your picture as well! Now point at the guard in the cave and mouse-click to fire.

Hit caps lock to always run. Take stuff go back to town. Save key sell rest.

T - to rest. Go back in. To the left - slaves - let them free. Baadargo, Okaw and Banalz.

Now go hard left from platform into nook. Find a rat to kill plus a skeleton with coins and a thief ring (right below first 2 mushrooms on left). +5 agility, +5 speed, +5 personality. Jump in water, swim under tunnel and come out at gate. On other side is guard with missiles plus a stash of stuff.

The final guy in cave - mage. Kill and get all stuff from chests. Jump on them to get the stuff on top too. In the next room, pilfer the crates on the dock. Then swim under water by crates to get stuff off skeleton (under the water) and money in chest in next area.

Note that when have moonsugar and skooma (refined moon sugar) Arrille won't trade so drop them on floor before trading. Skooma makes you fast and strong, but clumsy and stupid.

Now by selling all of this you have around 750 gold and are pretty set with Seyda Neen.

Elder Scrolls Morrowind Walkthrough