Reply to reserving a venue: any tips and expectations?

I'm throwing my 30th bday party soon and ideally, would like to reserve a venue's space so that my friends and I can DJ there. The hard part is that it will be on a Saturday and some places may already have resident DJs or other DJs booked. FYI, I'm in NYC.

I've reserved tables in the past, but I haven't reserved an actual space. An old coworker mentioned that he reserved the basement floor of a venue with a minimum bar tab of $4,000!! All-in-all, I'm not looking for anything fancy, just any bar that can accomodate DJs.

I checked out How to launch a Club Night: Part 1. here on DJTT, but my situation pertains to more of a one-time private party scenario. I'd like to know if any of you have any knowledge of what's expected in general or in terms of HOW the cost may be negotiated, i.e. bar tabs/fees or door cover (I don't want to have to charge my friends to come to my own party ).

For those familiar with NYC venues, I'm considering:
-Fat Buddha
-Bar 13
-Affaire
-People
-The Delancey
-White Rabbit (suggested to me)
-Tammany Hall (suggested to me)