I round up and purchase more. It sure makes those cutting mistakes easier. Because of this, I usually have something odd left over and I gave myself permission to give the extra away at the free table at Guild. I made the quilt I intended. No need to try to make placemats or some other small item to finish up the fabric line. I have changed my tactics. Now instead of purchasing a precut and 2 yards, I now purchase a precut and two one yard coordinates for either border or adding more blocks.