Affordable elopement in Nantucket ideas/tips

Hi! Looking for coordination tips and advice for an elopement in Nantucket.

I've hear Bryant Point is great (and free) and then maybe we go back to the Airbnb and say our "I do's" in front of parents/grandparents in the backyard of whatever house we rent. I think my fiancé and I would do private vows, our friend is marrying us so we don't need to hire someone. We could rent two large Airbnb's I am thinking about 20-30 people would be invited of our closest friends and family and then after we could go have a nice dinner with everyone and then go out to the bars to celebrate. It doesn't have to be crazy.

My other thought was saying our private vows in Woods Hole at the top of the knob. I love the view up there, and maybe we do it on Thursday so its less likely to be crowded?

Thoughts? I'd like to make this as affordable as possible. 5-10k MAX. Just intimate, fun times and surrounded by the beautiful scenery of Nantucket or the cape.

Also, we would have friends pay for their portion of the airbnb. We've had so many do destination weddings and all guests were responsible for their share in hotel or stay so we feel this is fair, but let me know your thoughts on that too. We aren't pressuring anyone and know that those who want to be there will make it work.