eCommerce Assistant for Big Commerce, Amazon and Facebook listings

I am seeking an Assistant to help me grow my online store. Our web store uses the Big Commerce platform and we also sell our products on Amazon.

I am seeking someone to make our Facebook posts 3 to 4 times per week, write a newsletter to our email base 2 times per month, and create and manage our Amazon and Facebook advertising. The person selected will also assist in photoshopping photos or our products and making new listings on our Amazon and Big Commerce sales channels. Reviewing and revising the content of our products would be very helpful to us.
Additional work responsibilities that can be added later would be SEM and SEO.