I recommend the Land's End Stadium Squall. Great hood, so many pockets, longer length, has the walking slits positioned so that you don't get a wet bum if you sit on something that is still damp, did I mention those pockets? And it comes in colours other than black for better visibility to cars and an easier time at coatchecks as a small bonus. They even come in petite sizing.

I like Poshmark, but here I would be wary because you don't know enough yet about what you need and want in a coat and you can't feel them up to know if the material will work. Some wool looks nice and thick, but is such a loose weave that the wind cuts right through. You are going to land up with more than one coat, so if you see one you like as a fancy dress coat and you forsee that being a need, it might be worth it, but don't expect it to work out as your main coat. You can find lots of nice sweaters, sweater dresses, and cozy cute winter skirts that way though!