I actually have a few purse patterns that call for binding to hide the inside seam. It can be quite tricky but it's a much nicer finish than a liner. When I first made them I thought I wouldn't like them and that they wouldn't sell as well as the others. But actually they sold better and held their shape much better than the lined bags. Even after washed the bag still looked good. The binding almost acted as a frame inside the purse. Glue basting(water soluable) both sides of the binding in place helped to get accurate placing for sewing. Also if theres curve to the bag make sure that you use bias binding method with your seams at an angle. Using a 16 needle helps with the bulk and a heavier thread to add strength. With the bulkier seams you may need to adjust your presser foot presser as you would for jeans. Taking a hammer to the heavy seams also helps as long as you use it lightly, pounding like you are hammering nails will damage the fibers but a few light taps makes helps the seam to lay flatter and the stitches look much nicer .