Hello!
Well rather than yell at you as some have done, (hey people, I love Latin, Mantillas, and praying the Rosary as much as any other trad, but let me tell you that screaming is a great way to give a bad impression

) let me tell you about my situation.
I’m in an abusive family situation that is VERY hostile to my religious beliefs. I am the only Catholic, and that just “gives a reason” for the abuse I’ve endured since childhood. I’m also currently financially dependent upon my parents, due to only recently having graduated college. (debts, bad economy, etc etc although I do have an interview soon, and possibly a job if God wills it.)
My fiance, who is amazing, and is taking RCIA and is REALLY growing in his faith (I can’t believe how much just a couple of months has changed him!

) is close to having his own apartment and is able to be financially independent. He is a kind, generous, intelligent, and amazing man.
I am also considering co-habitation,
but only with a dispensation. However, let me tell you right now that a dispensation is a very long shot, even in my case.
Only you know all of the reasons you want to live with your future spouse (and if that person does not want to be a future spouse but wants to live with you…RUN). If you want to live together, get a dispensation.
If you are granted a dispensation, it is still an irregular situation. You must both agree to live as brother and sister, sleeping in separate rooms, and possibly it might be a good idea to get a good Catholic roomie. It would probably be a good idea to go to weekly Confession as well. You are still causing scandal**, and living in near proximity to sin.
However,
please think this through. As amazing as Mr. Serrano is, and as much as I love him and would love nothing more than more time to be with him, I have many reservations about living together with him. Mr. Serrano is a good man, but both of us acknowledge that not giving into our desires (we may not be having sex, but that doesn’t mean we don’t want to!) would be extremely difficult.
In any case,
before you move in with someone, ask for a dispensation, and be open to whatever the Church in her wisdom tells you. If you are not granted a dispensation, don’t be bitter, but take it in stride, and don’t take it personally.
Co-habitation is extremely difficult- I’m a product of co-habitation. It has the potential to complicate the **** out of everything. Even if you get a dispensation, it will be difficult to live with that person in such an irregular situation. The temptation to act as if you were husband and wife, even in non-sexual matters, will be great.
**About scandal: Okay…here’s the thing. Nowadays, if you go on more than three dates, everyone assumes you’re having sex. Having been with my fiance for nearly 4 years, EVERYONE thinks we’re having sex, and it doesn’t matter at all what either of us say. I’m so sick and tired of hearing everyone tell me about condoms it isn’t even funny. The only satisfaction I get is when I tell them that not only am I virgin, neither me or the Mr. are ever going to use condoms, birth control, or anything other than NFP in grave circumstances. So when people go on the whole “what will others think” argument, I tend to roll my eyes. Yeah, whatever. People think that first comes sex, then comes a possible commitment, then comes a baby, and a few years down the road perhaps a court marriage comes a long just in time for you to divorce.

It doesn’t matter what people think…however if this is a stumbling block to people I’m perfectly fine with reiterating that no, I’m not having sex.
No, I’m still not living with Mr. Serrano (yet/possibly if we are granted a dispensation), and no, we haven’t had sex. If I do live with Mr. Serrano, I will explain the dispensation, what it is, might possibly give a reason for it being granted depending on who is asking, and will do my best to show that we are indeed trying to follow Catholic teaching.
I will say this again, though: I don’t particularly relish the idea of living together before marriage, dispensation or no, and I don’t recommend it unless the circumstances are very very very dire. Be open to whatever decision the Church makes, and accept Her authority.
And yes, if you do just up and live together before marriage, you will have to go to confession and arrange that before receiving the Body and Blood.
If you’re just doing this for financial reasons, let me tell you- if God wants your marriage to happen, it will happen. Just pray and work hard, and you will be taken care of. Don’t lose faith even when you don’t feel it.
Hope that helps!