Hi, this is a pretty simple project to describe. WooCommerce (a free eCommerce WordPress plugin from WooThemes) has a built-in widget called Layered Navigation. You can see a bit of detail about it here: [url removed, login to view] You can also download the WooCommerce plugin and test it out yourself (there are free themes for you to test).
Here's the project: I have an attribute called "Size" on my store and I need the layered nav to only show products that are in stock or are available via backorder. By default, the layered nav shows products even if they are out of stock and not available via backorder. I need a better way for customers to find what is available in certain sizes without visiting a ton of different pages. In addition, it would be fine for you to remove the "counts" from the page whenever any filter is applied (so counts would only be shown when no filter is applied). That should help with performance. The deliverable for this project is a new widget only showing "in stock" and "backorderable" product variations. You can start with the layered nav widget to help cut down on coding effort.
I can't allow you access to my store as a testing environment or my server. You will need to set up your own installation of WooCommerce on your server. I will help you fill it in with some fake data for testing purposes though, if you'd like.
Please don't submit a copy and paste bid. Give me some indication that you can do this outside of the fact that you have worked with php or wordpress before. Thanks!