I went through the process 8 years ago and did it myself, and what I found is that an agent can help you with what paperwork to fill out, but basically it’s all you having to to all the footwork finding proof of relationship and submitting it all, so I didn’t think an agent or a lawyer were worth the cost, since it doesn’t speed up the process anyway. I used a website that was completely free and walks you through step by step. Good luck to you.
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