Cost basis, depreciation and mortgage interest allocation when renting out part of home

My daughter bought a duplex last year. She lived there and rented out part of the property. In the Depreciation and Amortization Report, the cost basis generated by TurboTax is not the prorated percentage of the cost basis of the property less Land value. How is that Cost value calculated? On Schedule A, TurboTax did not prorate the mortgage interest but gave her the entire deduction of mortgage interest and points reported on Form 1098.  On Schedule E Worksheet, the mortgage interest was prorated with the proper amount allocated to personal use. Is Schedule A correct?