When you are buying a flat from a builder in a building under construction, you have to check the following:
 
1) Approved plan of the building along with the number of floors.
 
2) Make sure that the floor of the flat/apartment that you plan to buy is approved.
 
3) Check whether the builder is the owner of the land or if he has made an agreement with the land owner for the same.
 
4) Check with the specifications given in the brochure to the agreement for sale.
 
5) Check the applicable building byelaws in that area and make sure the builder is not violating those laws. Eg. Height, front setback, side setback etc.
 
6) Though not a legal matter check the credibility of the builder, whether the builder has any record of violating the applicable rules or not adhering to the specifications.
 
7) Ensure the urban land ceiling NOC if applicable has been obtained or not.
 
8) NOC from water and electricity authorities also have to be obtained.
 
9) NOC from lift authorities.
 
Agreement to Sell, Exchange of property, Conveyance Deed, Power of Attorney, Gift Deed, Partition Deed, settlement and Deed and Transfer of lease attract Stamp Duty on market value of the property.
Registration of a property in the corporation area will attract a stamp duty of 13.5%. In addition to this 2% registration fees is charged for registration in a corporation area.
In a municipality the stamp duty for registration is 12% and for panchayat area, it is 10%. of the value of the property.