A house can be owned by a single individual or co-owned by more than one person. It is not necessary that a co-owner should be a relative; even two or more friends can be co-owners of a property

However, co-ownership can be of two types, joint tenancy or common tenancy. Under joint tenancy, if one “tenant" dies, his or her share in the house goes to the other “tenant", or the survivor. 

But in common tenancy, if one tenant dies, his or her interest in the property goes to the legal heirs (as per the Will or as per the applicable succession law) and not necessarily to the other co-owner or survivor. 

Therefore, at the time of purchasing a property with a co-owner, ideally owners should properly disclose the nature of ownership and their respective shares, in the title document or sale deed, so that it’s easier to pass on a property to the next generation without any dispute.