Need help plz good 20' sailboat for a beginner need suggestions.?

I live in Marblehead, MA the sailing capital of the world and i was looking to buy a 20' sailboat for me and my mom. I would be the captain being that i took lessons and i might go back for more. I would take this boatout of the bay and into the ocean around marblehead, lynn, swampscott, and maybe even revere(if i have any bostonians). I need to know the perfect boat for this kind of recreational activities. It also has to cost $2000 or under. links are appreciated, thanks in advance!