Moving-In Landmines

So the Guy and I are thinking about moving in together.

Something that I have wanted and been ready for – for months and months. I never spend time in my place as it is. I get so frustrated shuttling clothes back and forth. And now I can help him pay his mortgage rather than spending a thousand dollars in rent for a place I sleep in once a month. All sounds good, right? But I know there are landmines I’m not seeing. Those of you who made this choice fairly recently – any warnings or advice before I sell all my stuff? The Guy and I definitely do not share the same sense of frugality, but we are very open with each other, and I think we are comfortable with some push and pull. He likes it when I help him grow and learn about his finances, and I know when to back off and just let him be him.

I think. Help… What are those moving-in landmines you don't see coming?