802.11n is the best choice for setting up a wireless connection that utilizes MIMO on non-overlapping channels. 802.11n is a wireless standard that offers faster speeds and longer range than previous standards. 802.11n uses multiple-input multiple-output (MIMO) technology, which allows multiple antennas to transmit and receive multiple spatial streams of data simultaneously. MIMO can improve wireless performance, reliability, and capacity by exploiting multipath propagation and spatial diversity. 802.11n also uses non-overlapping channels in both the 2.4 GHz and 5 GHz frequency bands to avoid interference and increase bandwidth. Non-overlapping channels are channels that do not share any part of their frequency spectrum with other channels. Reference: [CompTIA Network+ Certification Exam Objectives], 802.11n - Wikipedia

It's very common for ISPs to share common lines and such, especially when they are servicing the same physical location. It's therefore critically important to ensure path diversity, where the lines out of your ISP follow diverse paths to other routers. A common method for path diversity in smaller centers, for example, uses a fiber connection for the primary path and a very fast cellular connection as a failover. Use of both a fiber ISP and a different cable ISP can also lead to path diversity.

Attenuation is the weakening of a signal as it travels long distances and is caused when wave signals travel too far without help. As a cable run gets longer, the attenuation increases, and the signal becomes weaker.

UPS is an almost instant battery backup that prevents your devices and power from being interrupted, while generators have a longer start up time. Generators provide a much longer lasting backup power supply and can sustain your business for much longer than a UPS.