A condominium, or condo, is very similar to an apartment in terms of structure and multi-unit design. Often, apartments are converted to condos as the result of changes in complex ownership and management. Condominium owners own only the interior of their dwelling — from the walls inward — and, just like with an apartment, their home is attached to their neighbors’. All condominium owners who live in a particular complex share the financial responsibility for maintenance and repairs to the overall property and building exteriors, through payment of a monthly homeowners’ association fee and, if necessary, a special assessment requiring a one-time payment of a predetermined amount. Possible advantages to owning a condo include less individual financial obligation for exterior home repairs and a lower purchase price than a single-family home or townhouse. Disadvantages may include greater difficulty when selling a condo, as compared to single-family dwellings and townhouses, monthly homeowners’ dues, less privacy than with other types of housing and usually a complete lack of freedom to alter the exterior of the home in any way.