Models of equity?

Hi, we are a group of 6 adults and one child sharing 43 acres in Rhode Island. We bought the land in a hurry about 3 years ago, without all the leg work that makes these things smoother done in advanced (I know I know, but when the right place comes along you can’t pass it by!) Since then have been trying to piece it all together—our legal entity choice, our financial models, etc. We are especially stuck on what to do about members building equity and the buy in/buy out process. 4 members originally put different amounts in for the down payment. We are trying to figure out how to keep the buy in for future members low enough to welcome not just applicants with a lot of money, while at the same time allowing members who are leaving to leave with some of the money they put in/built in equity. I have looked around and cannot find anyone’s models of buy in/buy out anywhere! Does anyone have any examples of how communities are doing navigating the coming and going of members financially? I know some places you just leave with the shirt on your back, but we would like to offer a bit more financial stability to our members if possible. We would be very grateful for any assistance in finding examples to mull over! Thank you!