Nighthawk EX8000 Access Point or Extender. Ac1900 ?

Hi, I have several questions that I need help with. I have a Nighthawk TRI-Band R7900 router purchased
at Costco June 2016.
We have cat5 wiring throughout our house. So most everything that normally would using Wi-Fi like
Roku's are all hooked up with Ethernet. Our house is a two story and the router is upstairs in the office.
We have CenturyLink high speed 80 DSL. Most everything runs fine on Wi-Fi since it is only our IPhones
and IPads that we are usually using for wireless. We also have a garage door opener on the 2.4 band.
When I occasionally use Face Time in the downstairs family room I get a message that the signal is weak.
Other than that it has been fine. Last month we purchased a Ring Video Doorbell 2. I called their
customer support and had them walk me through the installation. They said the our Wi-Fi connection
was weak but it worked. I notice there is a lag time between when the doorbell is rung and when we
hear it go off.
So, I did research and decided to buy a Wi-Fi range extender. Since I had a tri-band Netgear router I
wanted to keep it all the same brand hoping to make it more compatible. I had seen that I could make it
an access point or a range extender. I was not sure what was the best way to hook it up.
So I decided to call Netgear. I figured they would know which one. The first time I called Netgear for
their recommendation the support person recommended to me to purchase an AC1900 Nighthawk
Mesh Extender. She said I would want to set it up as an access point not as an extender. I told her we
had a tri-band router. I also liked the idea that it I could use one password and Wi-Fi name and wouldn't
have to keep choosing which connection I was using. My router was already set to the smart connect
so that it would choose the best one for the device on its own.
I got it yesterday and called Netgear support and had the agent walk me through the installation. He set
it up as an access point. It took a good bit of time because apparently it didn't like the password I used
and wouldn't let it install until I shortened it. Also, he couldn't get it to install without having to name
the access point differently that the router one we had set up. After I got off the phone with the
Netgear support person, I was looking at the box the extender came in and noticed it is a Dual band
mesh extender not a Tri-band . I called back to Netgear and the person I spoke with said it would be
better to get a Tri-band and I could send it back and buy the Tri-band. She also said I would not want to
hook it up as an access point that I should have had it installed as an extender. I am so confused.
I started researching online again and now I really don't know what is best and nobody seems to agree.
I called Best Buy, and a couple of network computer stores in town today. Again, everyone says
something different.
I read that if you set it up as an extender, you lose about 50% bandwidth. It is just pushing the signal. I
read if you set it up as an access point with the Ethernet cord you don't lose anything. But the two
different support people I spoke with at Netgear said two opposite things.
I called Ring today and had them walk me through changing the connection to the access point that was
downstairs. It said I now have a solid connection. But now I have two different SSID Wi-Fi Names and
passwords.
So...I need to know what the right/best answer to these questions are:
1. Should I purchase the Tri-band Extender to match the Tri-band Router I have? Yes, this would be recommended.
2. Should I set it up as an extender or an access point? Depends if you want the main host wifi extended or not. What is the size of your home? Sq Ft?
What is the distance between the router and extender? 30 feet is recommended in between them to begin with depending upon building materials when wirelessly connected.
3. Is it better or worse to have it set up with two different SSID names and passwords? Kind of depends, most newer routers support signal SSID vs separate. However can be problematic for some IoT devices that only support 2.4Ghz. 
4. If I keep the dual band extender will I lose the third channel on my tri-band route? NO, the dual band extender just won't extend the 3rd radio.