Hypothetical cost of developing web based multitrack DAW?


I’m a second year sound engineering student. One of my final projects is to present a business idea to two prospective investors and I’m thinking along the lines of a social networking website like Facebook and Soundcloud but with a web based, relatively basic DAW for users to record/mix online.

How much would it cost to develop such software which should be relatively basic (8 tracks, maybe 4 native effects/processors, basic automation.)?

See: http://www.ohloh.net/p/audacity