Magento Multi-Store Inventory Extension

Hi There, We need to create a Magento extension that will allow the use of Multiple Stock QTY/Inventories per product on a multi site installation. Magento default system doesnt allow this and only uses 1 stock per item for the product across multiple site views and stores. We will need to be able to create several stock locations/warehouses depending on different store views and store websites (magento multi store) On the product grid we will need to show the QTY for the selected store view. If All store views are selected we will need to show all available stock. Need a feature so you can update multiple products inventory via Actions - Update Attributes We would like this to be an extension that we can share on magento connect. We will require future work for suggested updates, bugs and compatibility fixes. We like this to be very easy to install and very good code, we want the extension to do what it says. allow magento to have multiple inventories depending on store view. We hope you can join our team and if you have any cool features you would like to add to the extension please let us know. Please let us know the cost and how long it will take to create.