Like Jason said, find an older DJI Phantom on Amazon or Ebay and learn how to fly first. Believe it or not, you can't just power a drone up and start flying and they don't fly themselves. Release mechanism is the easy part, just clip a downrigger release onto the landing gear. You'll probably want to use braid, any stretch and it'll be hard to pop your line off the release when it's a few hundred yards out