Take Route 128 to Exit 26 in Waltham. Get onto Route 20 East, towards Boston; then take the first right onto Cedarwood Avenue. There's a bus stop at Cedarwood, and usually several buses parked there. The Chambers' residence, 33 Cedarwood Avenue, is on the right-hand side of the street.
Turn onto Cedarwood, and look for 33 Cedarwood Avenue on the right.