The team compared this to the cost of purchasing a RepRap free desktop 3D printer (averaging between $350 to $2,000), the $18 worth of printer supplies and factored in 25 hours of production time. From this, they calculated a household would recoup the cost of the printer within four months to two years, depending on the type of objects manufactured. This is based on the conservative assumption the household would only print around 20 objects a year.