Stitching in areas where seams have come undone.
Repairing frayed stitches or replacing frayed edges.
Extending envelope closures for pillows, in case they become tight.
Patches on damaged areas (with the customer's consent and with the understanding that they won't look brand new).
Extending curtains (where reserves were left, in case they have shrunk).
Redoing embroidery in a different pattern (if possible, in case of snagging).