Hmm. I'm not sure what the advantage would be over just creating communities on existing instances, then, if someone else is still going to be the admin.
Definitely upgrade the RAM. Also get at least two drives in RAID or ZFS or something so you can tolerate a failure. And keep backups too, if you can't afford to lose data.
That's the thing, it isn't poors shooting poors. House rep Gabby Giffords was shot in the head at a constituent event. House rep Steve Scalise was shot at a Congressional baseball game.
Actual traffic might be slightly different, but honestly on a LAN you shouldn't need to worry about latency. But you're not going to be able to run iperf3 on that router in any case.
Talk with the financial aid office. Usually those people are pretty good about getting it reduced, especially if you don't have insurance, and they should be able to create a payment plan.
Also check state law. Sometimes there's legal protection for you.
Hmm. I'm not sure what the advantage would be over just creating communities on existing instances, then, if someone else is still going to be the admin.