There a man was violent to a woman as a result of which the woman left the house taking the children with her while the man remained in the house. The man was required to pay rent for his sole occupation of the house. There is also the issue if the personal possessions of the parties to consider and whilst the home is often the major asset, the Claimant may feel entitled to a share in other assets. Trusts and estoppel aside, the ownership of a chattel will accrue initially to the partner who pays for its purchase. There is no presumption of advancement between cohabitants, although there is nothing to stop them making gifts to each other, which will vest ownership in the donee.
Income belongs to the earner.
These simple rules may be complicated if the purchase money comes from a bank account.