If one "AVN" is half the price of one "The Dark" CD, that means one CD of "The Dark" costs 12 * 2 = $<<12*2=24>>24.
So for two "The Dark" CDs, Alan needs to pay 24 * 2 = $<<24*2=48>>48.
So all CDs cost by now 12 + 48 = $<<12+48=60>>60.
The 90s music CDs cost 40/100 * 60 = $<<40/100*60=24>>24.
That means for all CDs Alan needs to pay 60 + 24 = $<<60+24=84>>84.
#### 84