This is the wild side of real estate investment. Real estate traders buy properties with the intention of holding them for a short period of time, often no more than three to four months, whereupon they hope to sell them for a profit. 

This technique is also called flipping properties and is based on buying properties that are either significantly undervalued or are in a very hot market.

Pure property flippers will not put any money into a house for improvements; the investment has to have the intrinsic value to turn a profit without alteration or they won't consider it. 

Flipping in this manner is a short-term cash investment.

If a property flipper gets caught in a situation where he or she can't unload a property, it can be devastating because these investors generally don't keep enough ready cash to pay the mortgage on a property for the long term. 

This can lead to continued losses for a real estate trader who is unable to offload the property in a bad market.

A second class of property flipper also exists. 

These investors make their money by buying reasonably priced properties and adding value by renovating them. This can be a longer-term investment depending on the extent of the improvements. 

The limiting feature of this investment is that it is time intensive and often only allows investors to take on one property at a time.