Too many factors for a simple answer. If you include editing and services very expensive. Simple printing can range from $2-$20 depending on images etc.
There are services, but it’s very hard to do high quality at home.
Not unless it’s one page.
Ingram Spark and Amazon are the most common.
Only if you don’t own the rights to it and try to profit.
Depends on font, formatting, page size. Too many factors to answer that. For example if you put one word a page, its 50K pages.
Not much. Most others do it on the side.
Like 1 page? Still depends on some factors. Talk to a few services industry is pretty standard.
Depends on the book and the person who owns it.
You can, it just costs more to print.