Setup External API access to add/modify products

[SCOWARD]

We are partnering with a local distributor and we'd like them to be able to be able to add hundreds of products to our Shopify site.  I've looked into creating a PRIVATE APP, and enabling Basic HTTP Authentication through a URL.  I've provided ADMIN API Access to Product, Product Listings, and Inventory.

Is this sufficient to allow them to build products on our site?

I'm a novice in this arena, so I apologize if I'm asking a dumb question.

Thanks in advance.