Best extender to get and how hard to install?

If your ISP modem already has a router and wif built in, This would be a double NAT (two router) condition which isn't recommended. https://kb.netgear.com/30186/What-is-Double-NAT
https://kb.netgear.com/30187/How-to-fix-issues-with-Double-NAT
Couple of options,
1. Configure the modem for transparent bridge or modem only mode. Then use the Orbi router in router mode. You'll need to contact the ISP for help and information in regards to the modem being bridged correctly.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ/ExposedHost or IP Pass-Through for the IP address the Orbi router gets from the modem. Then you can use the Orbi router in Router mode.
3. Or disable all wifi radios on the modem and connect the Orbi router to the modem, configure AP mode on the Orbi router. https://kb.netgear.com/31218/How-do-I-configure-my-Orbi-router-to-act-as-an-access-point and https://www.youtube.com/watch?v=H7LOcJ8GdDo&app=desktop 

Your Orbi should be good enough to handle wifi coverage and guest mode with out the addition of a extender. 

What is the size of your home? Sq Ft?

What is the distance between the router and satellite(s)? 30 feet is recommended in between RBR and RBS to begin with depending upon building materials when wirelessly connected. https://kb.netgear.com/000036466/How-far-should-I-place-my-Orbi-satellite-from-my-Orbi-router

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Interested13 wrote:

Hello - I'm not an IT specialist, so forgive me if I'm not using exact language here.... I  have an ORBI router RBR50 and a satellite (if that's what it's called) RBS50. We have a Comcast modem which provides a duo 2.4 and 5.0 Ghz speed. I created a guest network through the Orbi app that is dedicated 2.4 so my landscape irrigation system (Rachio) would connect  - it was disconnecting as the network fluxuated from 2.4 and 5 and Rachio told me I needed a dedicated 2.4 network. The name of the guest network is the same as the main 2.4/5.0 network with the word "guest" after it. I was wondering if I could get a wifi extender to make sure the 2.4 guest network got a stronger signal in the garage - was thinking I'd put it in the kitchen next to the garage. 

Questions:

• Can I "boost" the signal of only one of these? The dedicated 2.4 guest OR the duo 2.4/5.0 main one? Or will the extender boost both? If it would only boost the 2.4 guest network, then if using wifi in the kitchen, we'd have to switch to the 2.4 guest network. If we do that, then maybe our Sonos (which runs off the 2.4/5.0 non-guest network) wouldn't work?
• If I buy the plug in extender (like the small size and idea of being able to move this around)  - https://www.netgear.com/orbi/rbw30.aspx - which appears to only provide coverage for speeds up to 2.2 Gbps, will this slow down my whole network? I read this somewhere: "RBK50is AC3000 and the RBW30 is AC2200. The backhaul is also different and Tri-band vs Dual band. When mixing, your network speed capability will be limited to the max of your lowest device. 
• If the above would slow my overall speed down, do I need to buy another RBS50 instead? I don't think I need the ports... I just want to plug into power; don't have hard wired internet cable anywhere but to the main RBR50....https://www.netgear.com/orbi/rbs50.aspx.
• So - OVERALL question is 1) which extender should I get and will it boost both the guest 2.4 and the regular 2.4/5.0 network? 
• I just don't want to mess up the great network speeds we have with our regular 2.4/5.0 set up...

Thank you for any thoughts...

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