guides
Placement types
What each kind of placement is, what it costs, and what to check.
Guest posts: what they are, what they cost, when to buy one
A guest post is a new article on someone else's site with your link in it. What it costs across every marketplace, who writes it, and what to check before ordering.
Link insertions: a link added to an article that already exists
A link insertion places your link into a published article. Why it is often better value than a guest post, what it costs, and the one thing to check about the host page.
Niche edits: the same thing as a link insertion, mostly
Niche edit is the marketplace term for an insertion into an existing article. Where the two differ in practice, what they cost, and what to check.
Homepage links: a link on the front page, for a period
A homepage link sits on the publisher's front page, usually for a month or a year. What it costs, why it is priced differently, and what it is actually good for.