I bought a ton of Harlan's silver age comics about 10 years ago. At the time he wasn't ready to sell his GA stuff, for sentimental reasons. (He was really into Fawcett Comics as a kid).
I've been to his house several times and there is MUCH more collectible goodness. Tons of original art on his walls, toys, sculpture, movie posters, etc.
J. Michael Straczynski is the executor of Harlan's estate and the plan is to turn his house into a museum, of sorts. If you've never seen Ellison Wonderland, it's a thing to behold: