See the Cabana Deed Skip page.
Simply use a skull hammer jump attack to hit the wooden pegs through their respective adjacent walls. This avoids having to navigate your way through the sewers in order to get past the gates.
Use a sidle to clip part-way through the bars and then finish clipping by rolling. This is particularly useful if you are skipping the skull hammer in a Low%, and is the only part of the Cabana Sewers that otherwise requires the skull hammer. In any other case, it should not be used as the above method is faster.
You can alternatively skip the Skull Hammer Requirement with a very difficult L-Slide Clip to go OoB, and from there leaf to the last ladder. This also skips all Cabana Sewers at the same time.
After obtaining the treasure chart in the Cabana, backtrack to the hole that is located just behind the chest (follow the wall on the left of the chest to find it). Drop down the hole and sidle behind the ladder. Pull out the hookshot once you're behind the ladder. You wil notice that you are now able to aim out of bounds, so just aim at the only hookshottable ladder you can see and get pulled to it. Now repeat the process again with that ladder to hookshot to the chest containing 100 rupees. If you want even more rupees, store that chest. Thanks to chest storage, you can now hookshot through the wall on your left to another ladder. Now, jumpslash and you will notice that you will start swimming. You can now clip out of bounds and leaf to reach the pots containing around 70 rupees. Then go towards the crawlspace to once again hit water and clip back to the entrance. Leave the area to collect the rupees from the chest you stored.