Hi,
I'm an expert software developer and have been working with several clients, particularly from Australia, UK and US who had similar system requirements. They had their own Excel spreadsheets with formulas and wanted me to build a full blown subscription-based Web system they could use to sell their service. I can provide you with samples and logins for various systems to test out or do a demo over Skype or Teamviewer.
I believe if you want to take it to the cloud, you should build a system on top of it, not just utilize scripting languages and spreadsheets. Give me a chance to discuss this further, and to understand what are your requirements and vision for your inventory management app.
Looking forward hearing from you
Boris