Help! Small Town/Small Biz Challenge

Working in a small office with high traffic is a challenge.  We are small town with a friendly vibe.    We've built businesses contingent on meeting people's needs.  Our biz's require sincere interest in other people, hearing their wants/needs.  Our businesses foster connections whether it's with the friendly competitor down the street, the vendors we work with, the customers themselves or even the locals we've come to know through our biz's who pop in from time to time.  This is such a breath of fresh air from the corporate world I left where people/customers were merely a number.  ​However, I do need your help. 

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​I'm learning there are people who have no consideration for the fact we are, indeed, running a business.  They treat us like a captive audience with nothing better to do than listen to them rattle on when the transaction should have been polite and brief.  I don't mind the occassional pow wow, hell, I enjoy a lot of these people and some of them I depend on to help me in my biz.  Yet, I also need people to be respectful of my time. 

I've given clear indications & verbal confirmations that I need to return to work.  I've politely excused myself, I've shut my office door, I've gotten the "rescue" phone call lined up.  I've had vendors who think it's OK to open my door when it's closed or approach me while I'm on a biz call and one which is like family so he feels entitled to get his "hug" regardless of what I'm doing.  There's a complete lack of boundaries.  YES!  I have had a several talks with him, to no avail.  He has a bevy of health issues so he doesn't retain any such discussions.  There's also the side of me that says gosh, he may not be here tomorrow and I will regret denying a hug.

​I need to find a balance between building connections and cutting the convo.  I want them comfortable, but I don't want them TOO comfortable.  Sursly. I don't want to change my kind disposition, but I need to toughen up on these time vampires sucking away my day.  

How do you slay your time vampires?