Fair Housing Act (Title VIII of the 1968 Civil Rights Act, with amendments issued through Sept. 1988)

(c) For the purposes of subsection (b) of this section, a person shall be deemed to be in the business of selling or renting dwellings if-- 

(1) he has, within the preceding twelve months, participated as principal in three or more transactions involving the sale or rental of any dwelling or any interest therein, or 

(2) he has, within the preceding twelve months, participated as agent, other than in the sale of his own personal residence in providing sales or rental facilities or sales or rental services in two or more transactions involving the sale or rental of any dwelling or any interest therein, or 

(3) he is the owner of any dwelling designed or intended for occupancy by, or occupied by, five or more families.