In dealing with the Railroad faction in Fallout 4, PAM will ask you to turn over/align a settlement with the Railroad, making it "Mercer Safehouse". What/when/how is that settlement selected?
After multiple reloads and I keep getting asked for the same settlement… of which I have no interest in aligning that one directly with the Railroad. I would have thought the random determination had been selected when being given the mission?
Best Answer
As stated in this question, the safe house is determined randomly, from the list of settlements you have not yet taken over. If you have unlocked all settlements, it will be a random settlement you own.
Fallout 4 has a habit of pre-determining random elements, early. If there are other settlements you are yet to unlock, it has likely just set the original settlement in, earlier than the save file you are trying to reload.
You could try reloading an older save, and see if you can trigger a different settlement. As stated in the same answer, the Mercer safe house acts like any other settlement. There is no real disadvantage to loosing any specific settlement to the Railroad, this way.