Coats are the most visible thing you own, so the shape matters more than the label. Three silhouettes cover almost every occasion.
The overcoat is your formal option — long enough to cover tailoring, structured enough to hold a shoulder. The car coat sits at the hip and works over knitwear. The trench is the one you'll reach for eight months of the year.
Get the sleeve length right and everything else is fixable by a tailor.