I am excited for you...sounds like you have a plan! I am not educated on retail start up businesses. But I can tell you how I shop and maybe that can provide you with some ideas to draw people to your business. 1. Once I find a fabric I want to buy, I google it and try to find the best price on it. 2. If shipping costs are too high I wipe that online store off my list. 3. I must be able to see the fabrics together (I usually buy coordinating fabrics), so I love to be able to add the fabrics I am considering to a design wall.
It does seem to me that selling on Etsy or Ebay would be a good idea for you to work towards your goal. I don't know how popular the fabrics are that you plan to specialize in. I am not interested in those fabrics. Good Luck to you, hope all your dreams come true.