Home Club Picks Ad Agency: Home Club Inc., the Fullerton-based home improvement chain, handed its $12-million broadcast ad business to the Los Angeles agency Larsen Colby. Losing the business after several years was Los Angeles-based Davis, Ball & Colombatto. For Larsen Colby, the win more than makes up for the $6-million Subaru Dealers Assn. ad business that it lost earlier this year. Home Club, which has 73 warehouse stores in 11 states, plans to open 14 more stores in 1992. President James Halpin said the chain’s next campaign will focus less on price and more on service. Home Club plans to separately hire a service to place the ads.