/24 = 255 IPs = $0.47/IP/mo*
/23 = 2 x /24 = $0.43/IP/mo*
/22 = 4 x /24 = $0.39/IP/mo*
/21 = 8 x /24 = $0.40/IP/mo
/20 = 16 x /24 = $0.35/IP/mo
/19 = 32 x /24 = $0.30/IP/mo
/18 = 64 x /24 = $0.25/IP/mo
*Pay 36-mo in advance.
Pay 12-mo in advance and get 2-mo Free.