Looking for someone with serious php skills and very familiar with OpenCart

Looking to finish an OpenCart site that has been started. This site has a number of custom features and ways that it needs to work. I am looking for someone long term to assist with this site as we work through all the items. For now what I want help on is this: 1. Require login in order to see product categories or product items and details. Currently you have to be logged in to see the pricing but we need to take it a step further and not allow someone who doesn't have an account to be able to browse the inventory or categories on the site. 2. Limit the number of items that appear when you click on a category. We have several thousand items in the inventory though not all of them are commonly kept in stock. What we want to do is limit the number that will be shown to the user when they choose a category. I am not talking about the max number per page to display. For example.. if a category has 1000 items in it but only 500 are normally stocked that category would say there was 500 items in it. The other 500 that are not shown would only be viewable if someone searches for the item number using the search feature. The way we are going to do this is by using what we call a BIN number: If an item has a BIN number it is a product that is commonly stocked. If it does not have a BIN number it would only show if someone searches for it. These have been imported already as a sku if you look at an item in the admin, I believe. Though every item is showing up I believe this is because the last person imported it and items without a BIN were imported with a "0" BIN number. This could be solved by removing all the BIN's with 0's. Then you'd need to alter the cart so that it only displays those with BIN numbers on category views and only by search for those without a BIN. These are the first two items and probably the more challenging immediate ones. The rest will be easy and I would like to find someone who can do those as well in separate project posts on here. I will provide the URL to well qualified freelancers. Thanks! Tim