Lavalier Microphone (good sound is key): $19.59
Things supplies you may need to go with this set up:
You will need a camera. You can use anything just make sure it has a mic in jack. Camera's that don't allow this will force you to use the on camera audio which can sound distant with a ton of room echo. You can use your phone or tablet as a recording device as well. Most of these allow mics to plug in the headphone jack.
Make sure you have a dedicated SD Card for DSLR cameras.
Extra Batteries for your Microphone
Back up battery for your DSLR Camera
Extra bulbs: The lights we recommended take certain bulbs. You probably won't need them since they have a 5-year life but just in case:
Spare Bulbs 4 pack: $34.95