Honeywell Easy-to-Care 1-Gallon Cool Moisture Humidifier for $29.99 shipped. Here is a screenshot for your reference. It has 340 sq-ft humidifying capacity, holds up to 1 gallon of water and runs up to 36 hours per tank. It also has a top-fill design so it is easier to fill than most other humidifier. Most places have it for about $44.