回複：請教NIW，自己辦好，還是找律師？律師的作用是什麽，有多大？多謝。

Really up to yourself: how much you know NIW? and whether you can spend a great deal of time and efforts to prepare your materials? how strong of your background?

Attorney can help you, but you do most of work. If you want to hire attorney, I strongly suggest to be sure to get good one! In many cases, it is poor lawyer to bring your bad luck and pain - my lesson!