When shopping for a dehydrator, there are basically two options to choose from. Vertical-flow hydrators have a fan either in the lid or in the base that circulates heat either up or down through slotted trays on which you place food items. These tend to be the most affordable models out there. They're great for dehydrating batches of fruits and vegetables, but they are not as well-suited for making jerky or drying tougher vegetables, which require more of an even flow of heat all around. Trays on most vertical-flow models are dishwasher safe, however, which does make these easy to clean.