@rundocuri- I think that a cabin hook latch is exactly what you need for your backyard shed. I have used them before on various types of buildings, and they are basic and easy to use. They are also affordable and easy to install.
When you look for your cabin hook latch, just make sure you buy one that is durable so that it lasts for a long time. One way to ensure this is to buy one that isn't too cheaply priced. If you get the least expensive latch available, you are likely to find that it is made of thin metal and poor workmanship.