Creating Inventory with WordPress

can my friend update the inventory using strictly the CMS of WordPress

Sure, use custom fields to update the information. You just need to be able to code the theme in order for the figures to appear.
Having said that, if you’re setting up a store, and it looks like that, a WordPress e-commerce plugin or importing info from a stand-alone e-commerce application could be the answer.

Gratuity mercime. This won’t actually be a store, but hopefully it will eventually be carried into that realm on a slue of popularity.

Would you or some other folks out there be able to shine some light on clear, concise, real world tutorials on the web? The Codex has been my Achilles heel. Maybe you could refer me to a starting point, a WordPress refresh?

https://www.kriesi.at/archives/how-to-use-wordpress-custom-fields