Upgrade prices:
Upgrade from  1 to  5 slaves		$149
Upgrade from  1 to 10 slaves		$249
Upgrade from  1 to 20 slaves		$349
Upgrade from  1 to 40 slaves		$449
Upgrade from  1 to 80 slaves		$599
Upgrade from  1 to 160 slaves		$699
Upgrade from  5 to 10 slaves		$149
Upgrade from  5 to 20 slaves		$249
Upgrade from  5 to 40 slaves		$349
Upgrade from  5 to 80 slaves		$499
Upgrade from  5 to 160 slaves		$599
Upgrade from 10 to 20 slaves		$149
Upgrade from 10 to 40 slaves		$249
Upgrade from 10 to 80 slaves		$399
Upgrade from 10 to 160 slaves		$499
Upgrade from 20 to 40 slaves		$149
Upgrade from 20 to 80 slaves		$249
Upgrade from 20 to 160 slaves		$399
Upgrade from 40 to 80 slaves		$199
Upgrade from 40 to 160 slaves		$299