I will build an inventory forecast and reorder model in excel

An order or sales export from your platform, and your current stock on hand by SKU. Supplier lead times and minimum order quantities help. If you do not have everything, send what you have and I will use sensible defaults and mark them clearly in the model.

Twelve months is ideal and I can work with six. Under three months I switch to a launch-curve method instead of a straight forecast, and I will tell you which one I used and why.

That is where this earns its money. I explode every bundle down to its components, because a bundle is only as available as its scarcest ingredient. Most stockouts are component shortages hiding behind healthy-looking bundle numbers.

No. You get an Excel model you own outright, with no subscription and no ongoing cost. It opens in Google Sheets too if you prefer to work there.

Yes. Shopify, Amazon and wholesale can be planned together or split out, whichever matches how you actually buy stock. Multi-channel is included in the Full inventory system package.

Yes, that is the point. You update sales and stock, and the reorder flags update themselves. Nothing is hidden or locked. The Full inventory system package includes a call to walk you through it.