LOS ANGELES — A real estate company owned by Warren Buffett’s Berkshire Hathaway has agreed to pay $250 million to settle lawsuits nationwide claiming that longstanding practices by real estate brokerages forced U.S. homeowners to pay artificially inflated broker commissions when they sold their homes.HomeServices of America said Friday that the proposed settlement would shield its 51 brands, nearly 70,000 real estate agents and over 300 franchisees from similar litigation.The real estate company had been a …