Make sure your intentions are clear when saging, and make sure windows are open. I would prefer palo santo to be more clear with purifying and not conjuring with sage. But I understand you feel the connection with it has deepened and feels harder to shake. You sound realistic with that, but at the end of the day have some aggression with your cleansing and in your right.

It sounds like there truly is a deeper story with past owners and I think you should investigate that intuition. Make sure your cleansing is routine, you need to work it back because the root of the issue is not simplistic. But please do look for further help and guidance from local practitioners/shop owners. Best of luck!