Bond -  A certificate of debt issued by a government or corporation guaranteeing payment of the original investment plus interest by a specified future date.

Completion Certificate -  A legal document that is signed at the completion of contracted work to prove the company completed the work they promised to your satisfaction.  Never sign  until the job is finished.

Contractor -  A person or company who contracts to perform work on a rather large scale, at a certain price or rate, as in building houses or home improvements.

Designer -  One who designs, marks out, or plans; a contriver.

Dispute  -  A discussion in which disagreement is expressed; a debate.

Insurance -  The act of insuring, or assuring, against loss or damage by a contingent event.

Lien -   The right to take and hold or sell the property of a debtor as security or payment for a debt or duty. Many contractors will lien a property when the work is performed before payment is received.

License -  Official or legal permission to perform work or own a specified thing.  Authority or liberty given to do or forbear any act; especially, a formal permission from the proper authorities to perform certain acts or to carry on a certain business, which without such permission would be illegal; a grant of permission; as, a license to perform plumbing, to work on heating or air conditioning equipment, to sell and perform home improvements

Mediation -  An attempt to bring about a peaceful settlement or compromise between disputants through the objective intervention of a neutral party.

Payment Schedule - The act of paying with agreed terms. Most states have laws concerning payment schedules for home improvements.  Usually 1/3 down when work is started- 1/3 more when work is half done and the final payment upon completion.

Permit -  A document or certificate giving permission to do something; a license or warrant: a building permit. A legal document giving official permission to do something.

Right of Rescission -  You are entering into a contract that will result in a lien on, or a security interest in, your home.  Federal law gives you the legal right to rescind or cancel this contract without cost to you, but you must give notice of your decision to cancel within three (3) business days from whichever of the following events occurs last.
1. The date you signed the contract.
2. The date you received this notice of your right to cancel.
If the work is performed immediately and you sign a waiver of rescission to start the work before the 3 days you have most likely given away your right to change your mind.

Specifications -  A detailed, exact statement of particulars, especially a statement prescribing materials, dimensions, and quality of work for something to be built, installed, or manufactured.