How to grant location-specific employee access for online sales?

[BA7]

I am getting a booth at a consignment location to sell me products. The owner has requested employee access to my website so that she can do sales through that and I would receive payment instantly vs waiting for payout. 
I have created a second location and added inventory to that location. 
I’m not sure how to give her access to make sales only at the 1 location. I do not want her to have access to anything other than the product that is at that location. How do I do this?