Question Swapping existing router w/ a replacement; any issues?

[videobruce]

I'm replacing a TP Link Archer C7 with a Netgear R7000. My ISP is Verizon FIOS. I've initially setup the R7000 connected to my rarely used Laptop with NO Internet connection (purposely). Both have dd-wrt F/W.
What is the least hassle way of swapping Routers other than disconnecting one, then connecting the other? My concerns are with the ISP giving me a hassle one way or the other w/ the switch.
Also if the new router has some unknown 'glitch' and doesn't make the connection and I have to resort back to the original router, is that a problem with getting an new address from Verizon? I made NO changes to the WAN side of the settings

BTW, Verizon charges $5 per month additional NOT to use their router! (No, I'm not kidding)

 

[videobruce]

I did come across this from Techlicious;

Release the IP address on your Fios router

Releasing your IP address from your existing Fios router allows the ONT box to assign the correct IP address to your new router when you plug it in. According to the Fios technical support rep, this should happen automatically after a short period of time, but you might as well do it manually just to make sure. To manually release your IP address, follow these steps:

1. Log into your router settings either by typing https://192.168.1.1 or by going to myfiosgateway.com (method depends on what type of router you have) and entering your password. This information will be in the sticker attached to your router.
2. Click on My Network at the top of the page, then Network Connections from the left menu.
3. Click where it says Broadband Connection (Ethernet/Coax)
4. On the Broadband Connections Properties page, click Settings at the bottom.
5. Scroll down and click Release under DHCP Lease. Then hit apply changes."

Comments on that?