There are many boilerplate contracts for such a thing but you should consult with an attorney on this as sometimes it is very difficult to remove a tenant. You should consult an attorney who does most of his work for landlords who can draw up a legally binding lease.
You may also find some information here http://www.oaklandtenantsunion.org. You should also consult with the Oakland rent board as many of thes laws that protect tenants and landlords are local in nature.
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Technically, a lodger is a tenant in the landlord's own house. A tenant rents property owned by the landlord that is not where the landlord currently resides.
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