Get a Mac Pro Workhorse, Cheap
Half the price of a bare bones 2013 Mac Pro, the 2009 Mac Pro remains a solid workhorse.
Upgrade the CPU or add up to four internal hard drives in the drives bays or add up to three PCIe cards.
6-core 3.33 GHz Mac Pro from $1159 <==== 6 cores at 3.33 GHz