Chuck wants to know if he can connect a USB drive to his router. Leo says the router has to support it. It's not really "plug and play." And if it does support it, it may be pretty slow. But it can be accessed from any computer on the network, so it's kinda like a cheap NAS. If the router is open-source compatible, then Leo recommends going with DD-WRT or Tomato for the firmware. They have NAS features that could be most helpful.
Leo says he can build his own NAS with an old PC and use an open-source NAS software called FreeNAS. It's pretty good. But Leo prefers using Synology NAS systems. He can get them as big as he wants. They are a bit pricey, but the Synology NAS software is top-notch.
Another option is a cloud-based solution called NextCloud.