Looking for an app that allows me to set stock levels on products then generate a report that shows stock below/above the set number.
Prefer free options.
That's a good question! I can see how having that sort of functionality would be really handy for your inventory management. I think you are on the right track with thinking of an app to do this. I had a look on the Shopify App Store by searching for Inventory Management apps and I found a couple that look like they would suit your needs. Some of them include free plans also, as I know you mentioned you prefer free options:
Let me know if that helps! Keep in mind if you have any questions about an app, you can actually contact the app developers right from the app store page. If you click the Get Support button it will put you in direct contact with the app devs, who would be best equipped to answer any specific queries and to help with setup. Also if you can give me more information about your specific needs and why you would like to have an inventory app, I might be able to help you out with more resources.
We are from Sheet Master https://apps.shopify.com/sheet-master
We have a few inventory solutions on our app and are happy to evaluate if a custom solution is possible from our end. If you are interested, please install the app, and send us an email at firstname.lastname@example.org to take the discussion forward.