Live in is used with these nouns as the subject:
immigrant

Live in is used with these nouns as the object:
apartment, area, barracks, caravan, condition, cottage, dread, exile, flat, harmony, hope, house, ignorance, luxury, mansion, misery, palace, past, region, slum, society, squalor, state, terror, town, trailer, villa, world

Live-in is used with these nouns:
boyfriend, girlfriend, lover, maid, nanny