i listened to some of your beats and you defenenetly should not be selling exclusively for less then $300. Some of them could easily be sold in the $400-$500 range. Remember any beat you sell exclusively you can NEVER sell again. Assuming you listen to some of the people who earlier posted in this thread and sell your tracks for $100-$200 a piece. Someone like me could come along drop a grand on 10 of your beats. Then shop them to higher paying people, give to a music manager to shop or even just mass lease them for $100 a piece and in a year your 10 hottest tracks i bought for $1,000 could make me $10,000 or more.
basically, why sell a beat exclusively for $150 when you could just lease it non-exclusively 2 times for $75, make the same amount and still own the beat.