The Federal Aviation Administration (FAA) small drone rule became effective August 29, 2016. This rule eased the restrictions on Unmanned Aerial Systems (UAS) use for businesses by creating an FAA-issued "UAS Operator Certificate" which does not require a pilots license. HOWEVER, no matter which drone you buy, you’ll need to get clearance from the Federal Aviation Administration to use it for marketing listings. The FAA simplified the certification process in 2016, but you’ll still need to pass a test of aeronautical knowledge at an FAA-approved testing center. The FAA, which refers to drones as unmanned aircraft systems, also requires you to register your drone.
Make sure whoever you hire to use a drone on your listings is certified and their drone is registered.
Here's an FAQ on drones from the Federal Aviation Administration.