I have a friend whos in NH that has 80 acres and is building his dream house then wants to build a version of what your talking about here. This is a huge under taking.
You're going to want to first see if the municipality will even entertain you building STR's in their jurisdiction.
If yes, you will need the land surveyed to find lot lines and see whats possible to build.
You will need architectural and engineering plans for the builds.
One of your other main points of diligence from the beginning is going to be how will you get water, power, sewer/septic, and potentially clearing of trees and other land issues to get to build these properties. This can be a very costly and time consuming process involving multiple parties.
Then you will need zoning approval, permits, potentially an environmental test and so on. So this can cost tens if not hundreds of thousands before you even break ground on building.
Id get a great local realtor, a lender who specializes in these types of new con projects, an architect, an engineer, a builder/contractor who has the skills for a project like this, become close with the zoning department, the planning and building departments, the inspectors, and all your neighbors so you can have people on your team as you embark on this journey.