I bought it around January of 2011, when I knew I was going to move forward with the concept. It seems kind of tacky to share the amount, but it cost about 5-10x less than what most people guess, as the previous owner was extremely reasonable.
Amazing effort, @gmf & team. Super impressed & for years i have cribbed there is not a good way to save, with context, really AWESOME & insightful HN comments, for future perusal, archiving & searching.
IMHO, it does not seem tacky at all to share the amount, especially as a fellow hn reader explicitly asked to know it.
Obviously, you have every right, no to disclose it, for whatever reason.