I am a self taught amateur exploring 360 3D photography with a single camera. My basic setup includes one Sony a6000, a Rokinon 7.5mm shaved fisheye, a nodal ninja 3 and Manfrotto tripod. This rig allows for a minimum of 8 images (4 left, 4 right) which are stitched in ptgui and stacked top and bottom in Photoshop.
The basic challenge is time. It takes more than a minute to complete an 8 image stereo set with this rig. Even longer if attempting HDR. It is incredible how much will change in a scene in less than a minute. Tiny movements which go unnoticed in a 2D panorama will register in 3D as confusing depth cues which break the stereo illusion.
Time and stitching are the underlying issues in single camera stereo panoramas.