Consumer Portfolio Services Inc. renewed and amended an existing $100 million revolving credit agreement with Citibank and other lenders, according to a Securities and Exchange Commission filing this week. Loans under the agreement, which expires in August 2016, will be secured by auto loans that CPS holds now or may buy in the future from auto dealers. At the end of the two-year revolving period, the loans may amortize for one more year and then become due in full. Loans under the agreement bear interest at a floating rate equal to one-month Libor plus 5.50%; during the amortization period, the rate would increase to Libor plus 6.50%. CPS paid Citibank a $603,000 closing fee.