:param string hostname:Hostname of target purchased server.
:param number ram:Target amount of RAM for purchased server. Must be a power of 2 (2, 4, 8, 16, etc.). Maximum value of :doc:`getPurchasedServerMaxRam<getPurchasedServerMaxRam>`
:returns:Cost to purchase a server with the specified amount of ``ram``.
Giving any non-power-of-2 as an argument results in the function returning `-1`