Most quilt-shop quality fabrics now are above $5/yd, many are $6/yd and higher at wholesale.
When you're crunching your numbers, don't forget to figure in inbound shipping costs. Depending on where you get your fabrics from, these can add up to 50 cents a yard or more by the time you get them in your shop. If you're running a home-based business, your shipping costs will be about 20% higher. That's why a lot of shops try to specialize in fabrics that can be sourced nearby, from local distributors rather than getting them from clear across the country.
There are many many cost items that go into a sale that you never think of until you get into the business...
Good luck!