Well, it's not sealed, not exactly.
I took it out and played with it a few times, so the box has been opened. Long ago when we moved it got some packing tape on it. Not sure if that would hurt the value, but it's still better looking than some I've seen on the Web.
I'd need a list of contents to make sure no pieces are missing. I know the furniture, elevator and gadgets are intact, but there were lots of plastic I-Beams and clips to hold it all together. Plus I think there are a few extra chairs in there from my Starship Enterprise playset (which is also intact and in a slightly more crumpled box).
Maybe I should look at unloading this stuff. In all honesty, I can say that Mego stuff is way too crappy to hold onto even for sentimental reasons. I'm as nostalgic as the next guy -- maybe more -- but even as a kid I knew Mego toys left a LOT to be desired.
I mean, how can you really fight crime wearing oven mitts?
What I kick myself for almost daily is that I had that beautiful tin Batmobile (blue version) from Japan and somehow lost track of it over the years. And now I'll never afford it. How could I lose that and keep so much Mego junk?
Oh well. Maybe I can find someone willing to trade their Batmobile for the Foundation.