I was living in ferney-voltaire and a 2 bedroom cost 1300-1500 € to rent an unfurnished. You rely on bus F or 66.
I live in Geneva now in a 1 bedroom for about the same price in chf. It is mostly to go out with friend or to the lake on the summer after work. It also can help if your partner is looking for a job but in my case it is a personal choice not money driven.
If you are French native living in Gaillard I think it will make sense. I live in Annemasse previously and it was OK.