1. Get the property documents searched by an experienced lawyer,
2. Check the original mother deeds to ensure that the land has not been mortgaged with any Bank,
3. Ensure that the project has not been mortgaged with any Bank and if it has been mortgaged, collect a NOC from the said Bank for your buying the said 60 Sq.Ft floor and mortgage it with your Bank,
4. Apply for loan from a PSU Bank who will get the property searched and will inform you if there is any defect in the papers to be cured,
5. Ask for the sanctioned plan received from the Municipality and OC/CC issued by it certifying that the construction has been carried out as per the plan,
6. Get the Agreement check by a local lawyer before executing it,
7. The said agreement should have penalty for delay clause duly mentioning the last permitted date of handing over possession of the floor to you.