Grab the code in this tutorial from http://www.envision.io/wholesale-tutorial
Adding a wholesale area to your Shopify store is easy, and it doesn’t require an expensive app. Just copy and paste a bit of code and you’re all set!
This tutorial will help you set up a wholesale section in your Shopify store. This means that you’ll be able to make certain products, collections, and pages locked down so that only customers that you’ve approved as wholesalers will have access to them.
This method uses Shopify’s existing customer accounts feature–just tag the customer accounts who you’ve approved and they’ll be able to access your wholesale products, collections, and pages.
All of the code you’ll need and the written version of this tutorial can be found at http://www.envision.io/wholesale-tutorial