School library eBook market must reads

Reading up on this topic as much as possible. Our school has an Overdrive subscription for ebooks but, if we ever cancel, we lose access to every ebook we’ve carefully chosen/added to our collection. If we’re going to spend $1,000/yr on this, I say we use the money to actually purchase ebooks that can’t disappear if we decide a supplier is reaming us. Any other librarians have insight on this?