@fireweed@sakurajima.social i've lived there for quite a while, my best advice is to not look for something inside paris.
Since paris is not that big, and the metros and RERs go quite far, try to find something in the same region that is connected to paris by train, like villejuif, l'haÿ-les-roses, or even melun.
the train tickets will cost the same no matter how far you are or how many commuting trains you take as long as your trip starts and stop in the "île de france" region. It's all 2€50 for a ticket, or 2€ if you get automatic billing on your phone (idk if it works with non eu banks though, maybe revolut?).
the only thing to keep in mind is that transillien trains are on a different network iirc and they require you to buy the same ticket a second time if you commute to/from them.