This is the 281st most frequent Dutch word.
daarvan
"Daarvan" means "of that" or "from that" in English.
Here, 'daarvan' is used as a pronoun referring back to the books previously mentioned.
Hij heeft drie boeken gekocht en hij is dol op elk daarvan.
He bought three books, and he loves each of them.
In this case, 'daarvan' refers to the remaining pieces from the cake.
De taart is bijna op, maar er zijn nog een paar stukjes daarvan over.
The cake is almost gone, but there are still a few pieces of it left.
Here, 'daarvan' indicates possession or association, relating to the building's renovation costs.