There is no single magic number
Requirements vary by loan program and by lender. Some programs are built to work with lower scores; others expect more established credit. A score below one program’s guideline does not rule out every option — it rules out that program, which is a very different thing.
This is also why it helps to work with someone who can look across more than one lender. The answer to “what score do I need” genuinely depends on which door you are walking through, and there is usually more than one door.