Johnson Landlord-Tenant Lawyer, New York

A commercial real estate lease in which the tenant regularly pays not only for the space (as he does with a gross lease) but for a portion of the landlord's operating costs as well. When all three of the usual costs--taxes, maintenance and insurance--are passed on, the arrangement is known as a 'triple net lease.' Because these costs are variable and almost never decrease, a net lease favors the landlord. Accordingly, it may be possible for a tenant to bargain for a net lease with caps or ceilings, which limits the amount of rent the tenant must pay. For example, a net lease with caps may specify that an increase in taxes beyond a certain point (or any new taxes) will be paid by the landlord. The same kind of protection can be designed to cover increased insurance premiums and maintenance expenses.

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 basis of a contract. Consideration is a benefit or right for which the parties to a contract must bargain; the contract is founded on an exchange of one form of consideration for another. Consideration may be a promise to perform a certain act -- for example, a promise to fix a leaky roof -- or a promise not to do something, such as build a second story on a house that will block the neighbor's view. Whatever its particulars, consideration must be something of value to the people who are making the contract.

A payment required by a landlord to ensure that a tenant pays rent on time and keeps the rental unit in good condition. If the tenant damages the property or leaves owing rent, the landlord can use the security deposit to cover what the tenant owes.

An oral or written agreement (a contract) between two people concerning the use by one of the property of the other. A person can lease real estate (such as an apartment or business property) or personal property (such as a car or a boat). A lease should cover basic issues such as when the lease will begin and end, the rent or other costs, how payments should be made, and any restrictions on the use of the property. The property owner is often called the 'lessor,' and the person using the property is called the 'lessee.'

For income and capital gains tax purposes, the value that is used to determine profit or loss when property is sold. Often the basis is what you paid for the property, 'adjusted' to reflect improvements made or damage incurred while you own the property. See stepped-up basis, carryover basis.

An exception to a zoning ordinance, usually granted by a local government. For example, if you own an oddly shaped lot that could not accommodate a home in accordance with your city's setback requirement, you could apply at the appropriate office for a variance allowing you to build closer to a boundary line.

A determination of the value of something, such as a house, jewelry or stock. A professional appraiser -- a qualified, disinterested expert -- makes an estimate by examining the property, and looking at the initial purchase price and comparing it with recent sales of similar property. Courts commonly order appraisals in probate, condemnation, bankruptcy or foreclosure proceedings in order to determine the fair market value of property. Banks and real estate companies use appraisals to ascertain the worth of real estate for lending purposes. And insurance companies require appraisals to determine the amount of damage done to covered property before settling insurance claims.