Other essentials
Pockets can keep your hands warm and can also be used to store things such as gloves.
Water repellent shell for those wet or snowy days is highly recommended. These kind of coats are less breathable which will help keep the wind out.
Fit
When trying on a coat, make sure to move your body! Walk around, move your arms front to back, even twist to look over your shoulders. Check for ease of mobility and a comfortable fit. The fabric of a coat should not pull across the back area, around the hips or in the armholes. The sleeve length should extend beyond long-sleeved garments by at least half an inch.
Source;
The Godiva Chronicles