Edit:
新築の家を買った。今週を限りにこのマンションともお別れだ。
According to a thankfully posted comment, I realized that 新築の家を買った。今週を限りにこのマンションともお別れだ。seems to be sufficient and も adds the sense of 'also'.
How was that 'sense' expected to be added?....How was it figured out that it's a suitable time to add the sense of も to the sentence?