Robert is an aspiring filmmaker and he uses a DSLR to make his films. He's planning to upgrade to a better platform, but wants to know how he can improve his audio. Leo suggests Beachtek. They make devices that will allow him to run real XLR microphones into his camera's minijack and take advantage of better preamps as well. That's the best place to start.
Leo says Laura needs a camera that accepts external audio like the Canon Vixia. She can then plug the mic in. If Laura needs wireless, then the price goes up, and cheap wireless is a bad idea. Leo uses Lectrosonics for wireless microphones. They're very pricey ($1000 per mic), plus the receivers, plus the mics.