According to Fallout Wiki, when you try to open the door to the Charlestown Condo, the quest 'A Place to Call Home' is supposed to begin. A nearby object called 'hollowed out rock' is supposed to spawn a note to progress the quest. This note does not spawn.
This worked on my first playthrough (Anniversary Edition) before I installed UFO4P. Since I installed it, two additional playthroughs do not begin the quest.
I believe the patch broke the prompt.
Whilst the key to open the condo can be obtained via a console command, users miss out on the experience of the quest. Additionally, if this same issue applies to console, those users do not have the benefit of console commands.