Winter coats can be renewed with a little effort by yourself. Most of the problems occur with the inside of the coats such as a damaged or torn off lining. First of all try to repair the lining as much as possible. If you think it would not do any good you can replace it. First of all remove the lining and then select an appropriate lining material for it. If you know how to cut and stitch, you can do it at home. Otherwise contact your tailor to do it. As they would do a professional job on minimal charges.
Well first if your mom can't do it ask your grandmom or anyone in your family that knows how 2 sew very good.But if there is no one that knows how to sew just take it to the cleaners. Whatever you do do not put your Winter Coat in the wash machine that is a Big No No