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Can You Get Into Vault 81 Without Fusion Cores? [Solved]
McNamara will advise the player character that if they want to enter the Vault, they need to bring three fusion cores as a means of payment. Alternatively, the Survivor may pass a Hard speech check. If the choice is made to part with the cores, they will be compensated with 100 bottlecaps by the overseer.
Fallout 4 - How to enter Vault 81 without giving any fusion cores
Unfortunately,
Fallout 4 Vault 81 Entry (no fusion cores)
Here is the entry
How to cheat the fusion core deal at vault 81
Fallout 4 https://store.playstation.com/#!/en-us/tid=CUSA02557_00.