I stash my second janky NAS with my family in another part of the country. I ask my sibling to keep it powered on every week or so then shut it down after a couple minutes. If my main data storage near the capital city goes kaput, I’d phone my sibling to bring me my entire NAS (all expenses paid) immediately. My main stash is in my office which is only 10’ commute
Get an SBC (Orange Pi or Raspi), Radxa SATA HAT, spare router plus extra LAN cables, and a handful of SATA HDD. Hardware cost…let’s just put it at 300-ish USD. Electric cost, let’s just put it at double digit (at worst, low triple digit) kWh per month. I started out with an external HDD which downs me about 120 USD a couple years ago
Honestly, the best you can do right now is to select a handful of your best collection and download it using campus network (get your most trusty professor if possible to borrow his office to store your system while downloading it). 200 TB over 7 days would require something in the neighborhood of 300 MByte per second minimum (and 5 HDD running simultaneously to avoid bottleneck). That’s basically asking for the nigh-impossible: 2.5 Gbit (I suggest going for 4 Gbit) over network that you cannot really trust its throughput
Another option I could suggest is to rent something like Mega for a month or two while you download everything you can at your connection speed
Two, one in active use and the other has its main board (Raspi 3B) on loan for folks in my dept. I demanded, “As soon as we have 80-ish USD, we gonna replace that old clunker out for something recent using our department budget.” I could use a desktop PC as a case, tho (and use my Raspi-centered NAS as offsite backup back in my hometown).
Kinda-sorta…? The most sensitive data was more like 5-3-1: 5 copies (in my twin laptops, in my HDD-based NAS, one in my mobile external HDD, and one ‘offsite’ with my family back in my hometown). Then for my work data it was 3-2-1: main laptop, my NAS backup, and offsite (updated every holiday). For entertainment which are mostly loot from the seven seas, 2.5-1 rule: I stash bulk of them in my NAS (which I mostly stream to my laptop) and copy what I need to share with folks to the mobile HDD) and the other copy is also offsite