f-14 :
not sure what your homeplug is other than an ethernet cable.
anyways that switch you selected is unmanaged and does not come with a cross over cable which is basically a vice versa wire order on the ethernet plug, so you will need to make or purchase a crossover cable also.
communication wiring goes to the modem, modem via cross over cable to your switch, ethernet cables from your switches ports to your devices.
a managed switch does a better job of distributed flow control in reducing bottlenecks while sharing internet between several devices.
if you are only using one device at a time or devices that will not use the full amount of your internet MBPerSecond then it's not necessary at this time.
I realize you are only trying to be helpful but be sure what you post is correct.
Although homeplug is most commonly used as a ethernet cable it can be used as a mutiport switch by using more than 2 devices. Not that I would recommend it but it does work "most the time" to use your house wiring as a switch backplane
He is using a gig switch. All gig switches as part of the standard must support mdi/mdix. Most 10/100 also support this even though it is not required like it is for gig switches. This means you no longer need a cross cable. Good lucky trying to even find a cable that crosses all 4 pair.
A managed switch does not pass traffic any better or faster than a unmanged one. Almost no switch has an bottlenecks. The switch he lists actually has 16g of backplane speed. This means it is faster than all the ports transmitting and receive 1g of data at the same time. This is called non blocking or wirespeed. It is almost impossible to find any switch that does not run wirespeed even the very cheap ones. It is actually some of the manged ones with 10g ports that they over commit the capacity sometime to cut costs.
You really only need a manged switch when you need a feature such as vlans or you want to limit traffic below the port speeds for reasons other that raw capacity.