That doesn't sound flip in the context of you responding to what I wrote. It does make me curious though. Since you put it forward, can you identify what it is that would make that worth it to you? I expect that if there were a pool of people who were also willing to give all their money to Banksy to turn their houses into art, that there would be a variety of answers.
I think I can. The word that comes to mind is 'unique'. It would separate my (hypothetical) run-of-the-mill house from the masses, make it mine for a reason -- and it would energize me every single time I walked in the door. Spending time in my house would be that much more beautiful, and that's totally unquantifiable. (A bit similar to the difference between getting home every night to a TV dinner and a football game, or getting home to a wife and kids, if I may be so dramatic.) So it's not the value of the art, exactly. I'm trying to figure out in my brain if graffiti by a different artist would have the same impact -- I'm mentally replacing Banksy's art with some of my favorite Austin street murals, this is kind of fun actually -- and I've decided it totally would. But Banksy's street art is gorgeous and thought-provoking, so you know what you're getting. Hope that answers a bit.
So it's not the value of the art, exactly. That does answer the question and I actually think that given your answer, for you it is about the value of the art, though not in terms of financial value but rather in terms satisfaction via quality of experience.The word that comes to mind is 'unique'. It would separate my (hypothetical) run-of-the-mill house from the masses, make it mine for a reason -- and it would energize me every single time I walked in the door. Spending time in my house would be that much more beautiful, and that's totally unquantifiable. (A bit similar to the difference between getting home every night to a TV dinner and a football game, or getting home to a wife and kids, if I may be so dramatic.)