LETTER 1 filename1.txt Mail Stop 4561 August 10, 2005 Mr. Patrick W. Keene Chief Financial Officer AEI Fund Management XXI, Inc. 30 East 7th Street, Suite 1300 St. Paul, MN 55101 RE: AEI Real Estate Fund XV Limited Partnership File No. 0-14089 AEI Real Estate Fund XVII Limited Partnership File No. 0-17467 AEI Net Lease Income & Growth Fund XX Limited Partnership File No. 0-23778 AEI Income & Growth Fund XXI Limited Partnership File No. 0-29274 AEI Income & Growth Fund XXII Limited Partnership File No. 0-24003 AEI Income & Growth Fund 23 LLC File No. 0-30449 AEI Income & Growth Fund 24 LLC File No. 0-49653 Form 10-K for the year ended December 31, 2004 Form 10-Q for the quarter ended March 31, 2005 Dear Mr. Keene: We have completed our review of your Form 10-K and related filings and do not, at this time, have any further comments. Sincerely, Cicely D. Luckey Accounting Branch Chief