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An estate sale or estate liquidation is a sale or auction to dispose of a substantial portion of the materials owned by a person who is recently deceased or who must dispose of his or her personal property to facilitate a move.
Reasons for an estate sale 
The most common reason for an estate sale is the death of the property owner, and the consequent need to quickly liquidate the deceased's belongings. The survivors may have no interest in the bulk of the personal belongings left by the deceased, or may simply lack space to keep the belongings. In situations in which the survivors cannot agree to the disposition of tangible property, a court may order the goods to be sold in an estate sale with the proceeds to be divided among the survivors. Such a sale and division may also be mandated in the will of the deceased.
An estate sale may also occur because the property owner will be moving or has moved into a situation where he will be unable to keep his property—for example, a move to an assisted living facility, a retirement community, a rest home, or other living quarters.
An estate sale may also take place because of divorce, foreclosure, and relocation. In many regions hit hard by the foreclosure crisis, property owners are electing to liquidate their possessions. Oftentimes these individuals are forced to move to an apartment and or family member's residence.
Estate sales are usually conducted by a professional, for a percentage of the revenues. The liquidator may also charge the estate for the costs to give the sale, including advertising, marketing, research, labor, security, refreshments and other fees incurred in giving a successful sale. The presence of a professional liquidator may be necessary because the scope of the process is likely to be overwhelming to the survivors. The liquidator has knowledge and experience with pricing items, and general value knowledge of all types of household goods and personal property value, and the specialist's experience in disposing of unsold goods in an unsentimental manner after the sale. These professionals often take a percentage of the net proceeds, anywhere from 25% to 50%.
Admittance procedure 
Since many people may attend, not all people will fit into the confines of the house at the same time. The crowd must be controlled by a numbered sign-up sheet by the door or the issuance of 'numbers.' Typically the estate sale company will hand out numbered pieces of paper early on the first day to the people waiting in line. This is both a courtesy so that people may wait in their vehicles during inclement weather until the posted start time, and a way to prevent a 'mad rush' for the door when the sale begins. The holder of the sale will then call for the first 10 or 20 numbers. These people are admitted and they get first choice at the items. As they eventually leave, the next numbers are called and admitted. This way the company can control the number of people inside what is typically a cramped house.
Street numbers 
Typically one will see in an advertisement of an estate sale, 'street numbers honored' or 'street numbers not honored.' Street numbers are slips of paper that are generated by customers, usually dealers. These 'street' numbers are then exchanged for the real, official numbered slips of paper handed out by the estate sale company.