I am sort of surprised that pg chose movies rather than music. Movies are hard . You need a lot of things to make a movie. I liked Avatar. You can't do that kind of thing on the cheap. Actors, sites, makeup, lighting, special effects, etc. For music, you need the band, which are essentially founders from an equity standpoint, and own their own instruments already since they know how to play them. You need like $1000…
A $1000 recording won't give you great sound quality, not 24/96 K. It easy to marginalize a recording engineer until you try to record an album yourself. To get the the sound you want there are number of things you want to get right, the right equipment, the right space, mic placement, recording levels. Still not as expensive or hard as making movie, but not so easy either.
A lot of things that people think are "done in someone's garage" are either done by someone with very rich parents or produced by a relatively well funded company.