Reddit mentions of Rackstuds Rack Mounting System, 20-Pack

What you want is rack studs. Trust me these things are so much nicer than the cage nuts. I use them in my home lab.

Regular racks use the red ones. This will get you started! Rackstuds Rack Mounting System, 20-Pack https://www.amazon.com/dp/B00I347DXM/ref=cm_sw_r_cp_apa_i_ZIVqDbA0ASEMD

Note I'm just a user of these and live them I am not affiliated.

Square hole solution: https://www.amazon.com/Rackstuds-Smart-Mounting-System-20-pack/dp/B00I347DXM/

Overview on which holes they go in: https://www.youtube.com/watch?v=MkpU7yggz6M

You'll want a network rack. All racks are 19" between the rails and each Rack Unit (RU) is 1.75 inches.
Lots of network racks also come with locking doors and sides and most can even be wall mounted.

Network racks tend to have a shorter depth so they won't fit a full-size server, but they will fit most networking equipment and your SFF Dells.

Like this one for example


Obviously do some measurements and check that everything will fit. You can also buy rack shelves for the SFF Dells.

Always go with Square Punch rails (square holes on the actual racking bits). You can then use rack nuts and screws to secure your equipment to the rails. After you learn to hate rack nuts you can invest in some Rack Studs.

Craigslist and government deals are probably your best bet if you don't mind getting used gear for cheap.

$45 Startech 12U 2-post

$17 Rack Studs 20pc kit (optional)

Rackstuds Smart Rack Mounting System, 20-pack https://www.amazon.com/dp/B00I347DXM/ref=cm_sw_r_cp_api_TOmnzbC74G1RF

Thank me later.