The following are pamphlets that can be printed and bound at home using a stapler and US Letter (or A4) standard printer paper. This is a significantly cheaper option than ordering physical books if you already own a printer.
In my case, it comes out to about $0.25 USD for a 50-page pamphlet.
If it seems that the page numbers are out of order (i.e., the second page is directly next to the last page), don't worry, as that is the proper order for pamphlets of this type.
Guide on Producing Cheap Pamphlets at Home