Nri property sale transaction - tds query

Hi, I am planning to buy 2 bhk flat in Pune from NRI for cost of Rs 63 lakhs. NRI has Indian PAN card(Mumbai address) currently lives in Dubai. He purchased this flat from his NRE account as investment in year 2008. Address mentioned in property documents agreement between seller and builder is his Dubai address. I will be paying 33 from my own saving and 30 lakhs from home loan. Amount for this transaction will be deposited in seller State Bank of India Mumbai NRO account. Just wanted to clarify TDS deduction process for NRI after changes in place due to Finance bill 2015: 1. I will be deducting TDS @ 20.66% for this property transaction. 2. TAN (Tax Deduction Account No): Before deduction of TDS under section 195 I(buyer) will obtain TAN under section 203A of the Income Tax Act, 1961 by filing Form 49B. 3. Besides TAN I need to have my buyer PAN and seller PAN to deduct TDS under section 195. 4. TDS deducted by me(buyer) should be deposited through Form No / Challan 281 for TDS Payment on or before 7th day of next month in which the TDS is deducted. 5. After depositing TDS, the next step for me(buyer) is to electronically file TDS return by submitting form 27Q. 6. After filing TDS return, I(buyer) can issue TDS certificate ( Form 16A ) to Seller. Queries: a. Are above mentioned rate 20.66% and steps correct to deduct TDS? b. As a buyer do I need to fill form 15ca and 15cb before making payments to NRI for this property transaction or not? c. If I need to fill form 15CA and 15cb before making payments then do I need fill these form's two times first when I make payment from my own contribution and second when home loan cheque is disbursed? d. Is there any other form or tax I need to pay or produce for this property transaction? e. What proof's shall I keep with me for this transaction when I pay my income tax for financial year 2015? f. Do I need to take any written undertaking from seller for this transaction ? Thanks and Regards, Sonal