I killed Benny, got his keys. but i cant open the door to the subbasemant.

Where is the door of Tops Presidential Suite???

Walk from the entrance of the casino to where you encountered Benny, if you look to your left you should see some double doors to the suite.

i found it, thanks. what about the subbasemant??

The sub-basemant is used by Benny to escape the Tops, so if you did not give attempt to assault him and let him run, then the basemant will remain locked. Nothing that interesting in terms of loot, but it is neat to look at in there.

If you check your local map on your Pip-Boy, it shows that's actually an elevator that leads somewhere Underground vault 21.


I did try to find the other end at the Vaul but the only sign was another door that I coudn't enter, so I guess Vault 21 is the subbasemant.