"The tall man is outside."
Translation:A magas férfi kint van.
Giving a location with "to be" is pretty much a core argument which means the most neutral word order is to add it right before the verb. "Van kint", in the meantime opens the focus position to whatever preceding van. So, "A magas férfi van kint" answers the question "Who is outside?" rather than "Where is the tall man?" which is, by Hungarian logic, the most logical question you think of when encountering a sentence like "The tall man is outside."
"Van" can be left out when someone is performing an action in the 3rd person singular: "He is speaking Hungarian" = "Ő magyarul beszél" In this case, you don't have to say "van" (is), like you would have to in English (in fact saying "van" in this sentence would be incorrect)
But in the sentence "A magas férfi kint van.", "van" has a different meaning. It means "there is". Another example would be: "Van két almám" = "I have 2 apples" (a more literal translation would be "There exists 2 apples which are mine"... where "van" means "there is / exists" and "almám" means my apple")
So you see, "van" can also be used as "there is". And in this case, the sentence wouldn't make sense without it.