Brogan Real Estate Lawyer, Oregon

A service contract that covers a major housing system--for example, plumbing or electrical wiring--for a set period of time from the date a house is sold. The warranty guarantees repairs to the covered system and is renewable.

A legal doctrine that requires landlords to offer and maintain livable premises for their tenants. If a landlord fails to provide habitable housing, tenants in most states may legally withhold rent or take other measures, including hiring someone to fix the problem or moving out. See constructive eviction.

Principles of international law so fundamental that no nation may ignore them or attempt to contract out of them through treaties. For example, genocide and participating in a slave trade are thought to be jus cogens.

The act of changing a written contract when one of the parties can prove that the actual agreement was different than what's written down. The changes are usually made by a court when both parties overlooked a mistake in the document, or when one party has deceived the other.

A fee charged by real estate brokers and apartment-finding services in exchange for locating a rental property. These fees are permitted by law. Some landlords, however, charge finder's fees merely for renting a place. This type of charge is not legitimate and, in some areas, is specifically declared illegal.

A promise that pledges nothing, because it is vague or because the promisor can choose whether or not to honor it. Such promises are not legally binding. For example, if you get a new job and promise to work for three years, unless you resign sooner, you haven't made a valid contract and can resign or be fired at any time.

Any control over property. If you give away property but keep an incident of ownership--for example, you give away an apartment building but retain the right to receive rent--then legally, no gift has been made. This distinction can be important if you're making large gifts to reduce your eventual estate tax.

Insurance that reimburses a mortgage lender if the buyer defaults on the loan and the foreclosure sale price is less than the amount owed the lender (the mortgage plus the costs of the sale). A home buyer who makes less than a 20% down payment may have to purchase PMI.

A contract in which an owner leases her house (usually for one to five years) to a tenant for a specific monthly rent, and which gives the tenant the right to buy the house at the end of the lease period for a price established in advance. A lease option is often a good arrangement for a potential home buyer because it lets him move into a house he may buy without having to come up with a down payment or financing at that time.