Online auto retailer CarsDirect expanded its toehold in the home mortgage market on Thursday, announcing the purchase of two Web sites, BestRate.com and LoanApp.com.

El Segundo-based CarsDirect, a venture-funded company best known for its two automotive Web sites, CarsDirect.com and Autos.com, launched an online brokerage service called Loanstore.com last year. Another of its six Web sites, CheckInterestRates.com, displays the lowest interest rates from a host of lenders. (CarsDirect collects a fee from lenders for the referrals.)

Bob Brisco, chief executive of CarsDirect, said the two new Web sites, which were purchased from Myers Internet Inc. of San Jose, accelerated the company’s strategy of gobbling up ecommerce sites that involve “large ticket” transactions.

“We find the mortgage businesses to be very complementary with our auto business,” said Brisco. “An increasing number of consumers are looking to the equity in their homes as a less expensive way to finance their auto purchases, and there is overlap in lending institutions.”

He said the new sites will streamline the process of searching online for the best interest rates on a home mortgage.

The deal, for an undisclosed sum, also includes Myers’ mortgage technology platform that will allows CarsDirect to expand the sites quickly, and a marketing agreement with Myers in which the company can gain access to as many as 5,000 mortgage brokers.

Privately-held CarsDirect has 300 employees in El Segundo and Canada. It received a $280 million investment in venture capital in 1999 and has a large number of investors including Amazon.com, Idealab, Kleiner Perkins Caufield & Byers, Liberty Media, Oracle Corp. and Soros Private Equity Partners.