Septic systems require pumping every three years by a licensed pumper, as mandated by Minnesota law. The cost of septic installation can range from $4,000 to $15,000 depending on the property location and size of the system. It is recommended to consult with a septic expert before purchasing property to understand the specific rules and regulations surrounding sewage treatment systems in Minnesota. Alternative toilets, such as composting, incinerating, biological, recirculating, and holding toilets, are legal in Minnesota, but outhouses require a permit and specific rules. Graywater recycling is legal, but obtaining a permit can be difficult due to technical specifications. Understanding the regulations and costs associated with sewage treatment systems is essential for those considering off-grid living in Minnesota.