So i cant get the quest from logan, when i kill him he doesnt have the key to the anyone have any ideas?

It was glitched in my game as well, I never got the chance to get in there

Reload an earlier save from before you entered the basemant and try again.

You didn't kill Boxcars back in Nipton did you. [a powder ganger in the abandoned store]

Killing Boxcars spoils the quests he is part of, including one from Logan that gives you the keys. So if you kill Boxcars, the keys are not in Logan's inventory...

Did you actually start the quest?

The key isn't in his inventory until you you talk to Boxcars or possibly not until you get the radiation suits, Killing him beforehand won't work.

I can confirm this, having done this quest a few days ago. Technically the quest starts as soon as you pry out the info that he's looking for something there, however until you get the Rad Suits he won't say what it is he's looking for, nor will he have the keys you need if you kill him.

I ended up testing this completely on a whim; after talking to the guy he so pissed me off that I just had to blast him, and upon looting the corpse all he had was his outfit and weapon+ammo. I didn't really lose anything by doing so, since entering the basemant is an autosave point; I just reloaded and worked through his dialogue options again.

Killing him before finding everything he's looking for will fail the quest, however once you have the second key it really doesn't matter since you don't lose much XP by doing so and can still access all the loot.

NOTE: the items he is looking for are all 'quest item'-tagged, and will say 'NCR _____'; if you are planning on wasting him ahead of time do not pick these up as they can only be removed from your inventory by giving them to him. You will need to pick them up in the first building if you want access to the second one, though, as he neither gives you the key for the latter until that point, nor has it on his person.

Some people have a glitch where you can't talk to Boxcars about the quest and if this happens, I just killed the guy and stole the keys from him.