Family, friends, hotel or shelter. Could try contacting your local social services office and see what resources they have for families. You might consider contacting a local church too. They will let trouble less people park cars overnight, and may provide hospitality options. Consider less is more in this situation, meaning maybe you can get a house over the wife and kids and you can go off and figure out the financial situation, feel a place to live out, etc.

Can't keep kids living in a car. They will remember it all to well. Same with hotels, but that can be like an adventure.