The legal complexities of property ownership often cause problems on separation, divorce or at probate time.
Married couples have automatic rights which protect their occupation. To cover a situation arising when a marriage goes through a difficult time it is quickest and cheapest to issue a simple notice with the Land Registry that will ensure your house can not be sold or mortgaged without you being made aware.
Get your lawyer on the case to cover all such contingencies.
Joint tenancy is a form of ownership by people who share equal ownership of the property and have the equal, undivided right to keep or dispose of the property. Joint tenancy creates a Right of Survivorship. This right provides that if any one of the joint tenants dies, the remainder of the property is transferred to the survivor and this cannot be altered by a will.
Where co-owners are not married, or have made different contributions to the price, the preferred form of joint ownership will usually be as Tenants-in-Common. This means that the co-owners are regarded in law as having separate and distinct shares. They may give their shares away by will, and they may charge or mortgage them to a lender.
When renting if you live, or plan to live with another person, your council may give you permission to have a joint tenancy (private landlords may insist on a joint tenancy.)
Both or all tenants will share responsibility for things like paying the rent on time. If the other tenant(s) moves out of the property you are responsible for paying all the rent.