Check sewer availability
Some jurisdictions prohibit new onsite systems where public sewer is available or require connection under certain conditions. Confirm this before spending money on septic design.
Identify the permitting authority
Find the local health/environmental office and obtain the current rules, application, soil/site requirements, fees, and required professional credentials.
Evaluate soil and usable area
Gross acreage is not enough. Soil, slope, groundwater, floodplain, wells, water bodies, easements, structures, property shape, and required reserve area can determine whether the site works.
Protect your purchase
When appropriate, structure due diligence so the land purchase is contingent on acceptable septic/site approval. Local legal and real-estate advice may be appropriate for the contract language.
Use local rules for property-specific decisions
Septic design and permitting are location-specific. Before building, buying, repairing, adding bedrooms, or changing a property served by septic, confirm the current requirements with the local health/environmental authority.