[Lyscho] built a racing simulator cockpit based on a PVC frame but it took up a lot of space when not in use. His second generation is built inside the frame of an ottoman, meaning it can be stored right under your feet.
The pedals are fixed in place, with some padding below to rest your heels on. The cockpit chair and steering wheel are both adjustable to suit different drivers. They use a routed groove along with wing nuts and bolts, making it easy to slide them for adjustments. The ottoman itself is [Lyscho's] own creation, which just needs power and USB when in use, and has a padded top when not in use.
If you can’t use a real car as the simulator this is fantastic alternative.