I disagree with most of the above inputs. I presume you are buying a profitable business with good history. Your first focus should be preserving profit drivers; especially the culture. Hence let the seller continue in the office. Over 40 years I have sold businesses that have been ultra-ultra success. In each, the buyer has found an empty office near seller's office or added a desk in seller's office! The buyer who acts like a BOSS GUARNTEES FAILURE. I have seen many like that in my early days as M&A Intermediary. Today, we don't advance such buyer.

I agree with Mike and Avi. In my experience, showing respect for the founder/seller and humility in my first interactions with the team helped get our relationships off on the right foot.