Mid-range air purifiers with enhanced features for medium-sized rooms Air purifiers under $300 represent mid-range options with enhanced features suitable for medium-sized rooms. These models typically offer more advanced filtration systems, often including true HEPA filters, activated carbon layers, and sometimes additional technologies like ionizers. They may feature digital controls, air quality sensors, auto modes, and quieter operation compared to lower-priced units. This price range often provides a good balance of performance, features, and value, making these purifiers suitable for many households seeking effective air cleaning without breaking the bank.