Some more info:
Grammy museum: yesterday I visited the MJ exhibition down on the Olympic Boulvard. MJ has only one wall with appr. 7-9 costumes, majority of them owned by his Estate. Except two suites that is owned by John Branca. On the ground floor in the merchandising store you can get some MJ items licensed by Bravado or the Grammy museum (they are selling posters licensed by MJ Licensing Llc as well, hope the Estate people are aware of this).
Thriller house: the location where the famous video has been shooted is pretty empty now. Actually the house is falling apart and it's hard to even know if you are on the right place. Nothing shows the importance of that place.
Let me know if you would see actual pictures of the places and I will upload them.