• Property with deviation in constructed area

I was interested in a resale property in Chennai. The property is located in a prime location and the owner (say Mr. X) quoted a decent price. After paying token advance and checking the documents, I came to know that the apartment (which is located in the second floor) was given approval by MMDA for only 700 square feet for a 2 BHK whereas the builder (from whom the owner Mr. X had purchased) had constructed 1060 square feet and a 3 BHK. It's a clear case of a deviation against the plan. 

When asked about the same to owner, he doesn't sound convincing to me. Will this pose a threat in future?

At the time, the FSI for the land was 1.279. Currently, it seems FSI seems to have increased to 1.5. Can one approach CMDA for re-approval, sort of ?

I dont know whether to proceed with the purchase or not?

Regards
Mr. Bala