Begin by measuring a four-by-four-inch square on the outer lid of an eighteen-gallon storage tote, cutting out the plastic section with a sharp utility knife. Cut a piece of clear, six-millimeter-thick acrylic sheeting one inch wider on all sides than the opening. Apply a thick bead of exterior-grade clear silicone sealant around the cut opening on the lid’s top surface, press the acrylic window firmly into the silicone, and secure the corners using short, rust-proof machine screws with rubber washers. Line the bottom, walls, and the opaque portions of the lid interior with one-inch rigid foam insulation boards, cutting a five-inch round entry hole on the front wall. Place an interior baffle wall between the entryway and the rear sleeping nest, ensuring the acrylic observation window aligns directly over the entry hall rather than the dark sleeping compartment. Fill the rear nook with fluffy straw, snap the window lid securely onto the box, and place the shelter in a quiet, protected location.