Full T1 is $500/month here, my 6 Mb down, 512 Kb up cable modem is $90/month. My cable ISP (insightbb.com) also blocks 135-139 and 445 TCP inbound and outbound. My ISP at home only blocks 25 outbound like this, but all inbound ports are open. By blocking ports, they are technically offering a security service (bye-bye “common carrier” shield here), and if a user get’s hacked, that security service is deficient.”]
Source: https://taosecurity.blogspot.com/2005/07/what-does-your-isp-block-only-low-cost.html