You don't really need a toggle coat, topcoat, and a parka to last through the season. Two coats—one casual, and one dressier, will do more than enough. Find a style that works for you and wear the hell out of it, and then when the time comes, replace it. Give the old one to someone who actually needs it, like a homeless person. Plenty of places have coat drives each season, so hand down that style and get yourself an upgrade.
You Own More Jackets Than There Are Days in Winter