The administrator of the rights has set price minimums for titles by instrumentation. However, most buyers of print music, especially buyers of ensemble music, are primarily concerned with the quality and difficulty of arrangement, not finding the cheapest price. So price your title accordingly. You can also browse similar offerings on Sheet Music Plus to get a sense of pricing on similar titles.
Here are the current price minimums for copyrighted song arrangements:
$4.99: Piano (including piano/voice/guitar, piano solo, easy piano, piano duet)
$4.99: Guitar (including guitar tab, solo guitar, easy guitar)
$4.99: Instrumental solo or duet
$4.99: Handbell part
$12.99: Small ensemble
$49.99: Large ensemble