Illegal Construction in parking area

M planning to buy a flat in builder flat in dwarka mor new delhi. The land is of 160 Sqr yard and has total eight flats on it. Four flats are 2BHK (60 Sqr yards each) and four 3BHK (100 Sqr yards each). Builder is mentioning ground floor as a parking space. Since the building doesn't have any MCD/DDA approved map, there is one room set being constructed in almost 20 Sqr yards. He is giving us a car parking on registry. Also India Infoline is ready to give us loan on above mentioned building. Please resolve my below mentioned queries. 1.) Is it ok to go with a property which is Without approved map? 2.) As builder is to sale all four flats and by law after selling all the flats, builder doesnt have any right on property/Land/Building then in case of non authorized Map what consequences may flats owners face if builder is constructing illegal room set in parking and will give it to someone on GPA? 3.) Is it possible for builder to give us GPA/Agreement for our car parking? 4.) Is it valid if builder mentions "Reserve Car parking" in register or he has to mentioned the location as well in the registry? Please help me!!!