NORWOOD, MASS. — CarMax has acquired a $20 million development site at 212 Carnegie Row in Norwood to construct a new superstore. CarMax, a used-car dealership with more than 100 locations nationwide, plans to raze an existing 125,000-square-foot facility and build a new CarMax Auto Superstore on the site's 10 acres. Another 15 acres of wetlands will be preserved as open space. Elliot Ravech of Elliot & Co. represented the seller, CMI Property/Irene Realty Trust, in the transaction. Rob Grady of the Dartmouth Co. represented the buyer.