As of March 2015, Lowe's does not rent dehumidifiers. The Home Depot does rent two different types of dehumidifiers and a mold fogger through their tool rental centers, however.
Lowe's rents tools at stores in seven different states, but at present it does not rent dehumidifiers.
Some The Home Depot locations have 18- and 29-gallon-per-day dehumidifiers available for rent. These are not available at all locations, however. There is a store finder on the Home Depot website under the Tool, Truck and Equipment section that can be used to find the nearest location that rents dehumidifiers, dryers and mold foggers.