If you are looking for a safe place to hide your most valuable belongings, I recommend finding a vent in a random place in your house, where no one would even think to check for your stuff. Why buy a safe when you can just use your surroundings?
Step 1: Find a Vent
This is very straight forward, but find a vent in a low traffic area of your living quarters.... You may need a screwdriver to take it off.
Step 2: Hide Your Stuff!!!
Put your most valuable items in your vent. Now your stuff is safe!!!