In a totally crazy coincidence, later that night we ran into Steve Haise who is hands down the BIGGEST Van Halen fan we know (and maybe even in the world). He almost creamed himself when he heard where we'd been earlier that night.
We got to the building in question and fucked around pressing all the apartment buzzers until someone finally buzzed us in (Holly Golightly style, boyeeee). We weren't positive the intelligence we'd gotten was accurate until we got into the lobby and saw this sticker on one of the mailboxes (I shit you not!). He even calls himself DLR. Fucking amazing.
After a few knocks, it was clear that no one was going to answer. We figured that maybe everyone was out on the balcony deck with DLR and they couldn't hear us. We decided to head up to the roof and see if we'd be able to get a vantage point of the party from there.