Desing of query

Hello

Can we write sql query better than the below marked red

As the table Cust_acct_collateral table contrains multple rows w.r acct_no and case_no , it should return only one string (combination of all records)

Version : 11.2.0.1

select
ACCT.CASE_NO,
                                               ACCT.ACCT_NO,
                                               CLKP.CMS_CLIENT_NAME,
                                               REL.REL_NAME,
                                               REL.ADDR1,
                                               REL.ADDR2,
                                               REL.CITY,
                                               REL.STATE_CD,
                                               REL.ZIP_MAIN ZIP_CODE,
                                               DTL.AMT_PST_DUE AMT_DUE,
                                               DTL.CURR_BAL,
                                               DTL.TOTAL_PMT_DUE,
                                               trunc(SYSDATE) LTR_DATE,
                                               NODEXPIREDAYS EXPIRE_DAYS,
                                               trunc((trunc(sysdate)+ NODEXPIREDAYS)) NOD_EXPIRE_DATE,
                                               (CASE
                                                     WHEN REL.REL_TYPE_ID = 1 THEN NOD_MAKER_PP_DOC_CD