[denniskathyb]

Originally Posted by Hacker1

About 3 years ago, I purchased a new Netgear AC-1600 WiFi Cable Modem Router for my Xfinity Internet service. We are seasonal, and have been terminating our service every Spring when we leave, rather than putting it "on vacation" (to avoid the significant raise in rates when my "introductory" period expired). After successfully reconnecting for 2 (or 3, can't remember which) years, this past Fall, we were not connecting. Ended up having an Xfinity Service technician come to our house. Almost first thing he wanted to do was have me agree to rent one of their modem-routers. He connected their new modem-router in our house, it would still not connect to Xfinity's service -- until he replaced a couple of old connections outside. Then it seemed to connect fine. I asked if he could reconnect my Netgear AC-1600. His response was that due to some upgrades Xfinity had made in their service during the past few months, he was sure it wouldn't work, and assured me that the rental on their "good" modem-router is only $10 per month. We accepted the rental, which has since become $15 per month. I have never been 100% confident that my Netgear AC-1600 won't work any more, but have not taken the trouble to try to switch. Just to mention, we're in a patio villa (which to my understanding should not require as powerful a router as a larger house).
To answer OP's questions: (1) I've always used the combination Modem/Router, & been successful, except for the above-mentioned instance. (2) Rent vs. buy: Probably no one right answer for everyone. Depends on price you can buy at, and how much/how often technology advances beyond capability of the unit you buy. As to tax, with regard to the monthly billings, everything is lumped together, I assume taxes are levied on everything.

Finally, I'd appreciate any opinions of knowledgeable folks as to whether it is reasonable to believe that my 3-year-old Netgear AC-1600 is really obsolete??

About 5-6 years ago I purchased a NetGear nighthawk (modem/router combo). It works fine with Comcast, no issues. It's top speed is 800 mbps.
(Amazon.com) $200.00