My grandpa got a pool table in his basement in a very similar stair condition. To this day, I have no idea how beyond the fact that he had a come along tied to a 4x4 across the basement door. We just left it down there when we sold the house.
This actually happens. Had a relative that bought one of a row of townhouses being built back in the 60s. The company building the houses thought it would be a sweet incentive to include a piano with each one, so now everyones house in that row has a busted old stand up piano in the basement that's impossible to remove without some sort of demolition.
WOW. When the app popped up your comment, I saw the first sentence and I tried to guess which of my comments it was a response to. Then I went like "no way".
No matter how hard you try to come up with some surrealist bullshit, chances are someone had thought of the same and went like "this is a great idea".