Cost alone is usually the last consideration when choosing a system, because the cost factors are driven by the first four categories: Location, temperature/heat, ventilation/exhaust, toilet stool, capacity.

It can be all too easy to choose a composter model based on purchase price alone. It could be a costly mistake.

Of manufactured systems, the small self-contained composters are purchased for seasonal second homes and cottages. Because they are used only 14 to 30 days a year, they are much smaller and less expensive than large central systems. However, be careful when selecting any appliance composter for residential use. Yes, it might have been tested for a limited number of persons in continuous use by a small family, but you might soon become weary of the daily and weekly routines required to keep it operating well. Self-contained composters such as Sun-Mar composting toilet systems, are highly mechanized, but while they are small and lower priced, their operating, maintenance, and lifecycle costs can be much higher. The size of larger composters might require a significant modifications to your house. Consider those costs, too.