I'm a very small but successful online store. Each year I increase my budgets a little to align with my steadily increasing revenue, but I still struggle to keep my items in stock due to my budget. I prioritize the products that sell quickly, but other products that don't sell as well tend to run out of stock, which I know is frustrating for customers. This year my monthly COGS budget is $1000 and I've been overspending it by about $500/month, so next year I'm going to increase the budget to $2000.

I guess I just want to commiserate if this is normal for retail. :) Or is there a strategy for ensuring that I can restock at least a little bit of everything (and a lot of the items that sell quickly)?