own business in town; can i sell btc in person=2=person sales ??? legally ??

So i own a small service shop
we restore metal (sandblast and powder coat); not that that matters....but is it legal for me to offer the sale to acquire btc up at my shop?? i am a one man band shop and just like to keep a couple irons in the fire - i have lots of alt-coins and could offer them as well...

just curious about like if i need to get like an exchange license or something ??
im in small town in state of Vermont - most haven't heard of btc, but i can advertise in NH and MASS - and i see that there are a couple ppl doing it- but didn't want to ask them as i could potentially be considered competition in their eyes- perhaps

tried google and didnt see anything written up about selling / flipping btc as a supplemental income in/at your business

pls thx