So I did everything I could think to do, including killing house before LR... Yet I still ended up with his duster... WTH? The only thing I did for House was snow globes and get the chip... Then commenced to tell him the chip was mine and killed him with Nephi's Driver.

Vault 21 is considered both the House and Independent duster. The former for obvious reasons, and the latter because the Courier still wouldn't have been able to wrest control of Vegans the the Mojave from House, NCR and the Legion without the aid the House (foolishly) gave her.

to get it do what i did get liked by followers and brother hood of steel but dont do anything with NCR or Legion thats what i did to get the independent duster

Actually there are two separate dusters for House and independent. The independent duster has the 21 on the back and the House duster has the old world flag on the back and looks exactly the same as Ulysses' duster.

The way, from what I have read up on it because I also really want the independent duster if only for how awesome it looks and to get my allegiances(or lack there of), straight is all about your reputation with the 3 main factions: the NCR, the Legion and the Strip. I don't think that the Brotherhood or the Follower's enter into it. The important thing is to have either no or a negative reputation with all three of these factions. If you're already Idolized with one of them then kill a few of there troops and a Wild Child rep should be fine. I should say that I have not tested this yet and this is just what I have been able to find from google, the wiki and various forums.

If your karma is above neutral for any of the major factions that can cause a problem. I was Liked by CL and a Soft Hearted Devil by the NCR and I got The Legion Duster.

Exactly, as long as your negative reputation outweighs or is equal to your positive reputation then the indie duster is pretty much guaranteed. http://fallout.wikia.com/wiki/Fallout:_New_Vegas_reputations#Reputation is a list of all of the names you can get through reputation. Green is good, red is bad and black is neutral.

I got the 21 Duster while being accepted by NCR and idolized by the strip. I did save LR as the very last thing though, i saved Kimball and rigged the substation for Yes Man before starting it, so it was pretty obvious for what eding i was going for. Even for the game :hehe:

Also i tried LR with a fresh character (that i leveled up to 25 with console commands) with no reputation with anyone, seems like NCR is the default assumption of Ulysses.