I never even bother looking at "shared apartment" or whatever the other options are -- just "private home/apartment". Occasionally this has turned out to mean a private apartment (with a locking door) that is like an in-law apartment in the same house as the hosts live, and in a couple of cases in order to go up to "our" door we had to walk through a shared hall that was part of the host's place. But I would never choose to stay at a place that did not have a bathroom, kitchen, and locked door to ourselves -- way too much togetherness! Fortunately, AirBnB website makes it pretty easy to filter those out.