If you want to house everything inside your A2000 case, including the audio drive and 2 video drives connected to a Flyer board, you might want to consider buying the pre-formatted solid state solutions provided by DiscreetFX, instead of using big, heat producing SCSI hard drives that probably would not all fit into the original A2000 case and therefore cause you to need that Octopus cable and an external drive tower.
And "YES", setting up any kind of video editing system can get expensive. If you want cheap, you should just use a newer PC system and any USB or FireWire camcorder with free, or cheap software editors.
