Quarantine No Separate Room for Quarantine

So there's a beautiful little sow for adoption on UsedVictoria.com at the moment, and I have been contemplating adding a third to my pair for a while now. I want to rescue her so badly, her current owner keeps her in an aquarium!! :sad:

The problem is, my apartment is open-concept, so aside from the bedroom (which barely fits our bed and a dresser, never mind a piggy cage of any decent size) and the bathroom, there is no place to properly quarantine any new addition to our home. I wonder if I kept her in that aquarium (*shudder*) for the 3-week period in the dining room area which is a fair distance from the living room where the girls' cage is, would that be at all helpful? Or should I just get her into a proper cage ASAP, still as far away from the other girls as possible, use all other precautions (hand-washing, changing shirts when handling etc.) and hope for the best?

LOL my co-worker has just pointed out I could keep the new piggy at our office for the quarantine, I think she just wants an office pet!!!lolBut...come to think of it...so long as no one in the office has allergies...hmmmmm...