Builder is not refunding booking amount..

2013 my friend is builder he offered me a plan.... to pay 2. 5 lk and book a flat and then after the construction is completed i can either sell that flat at the market value pay him decided value of the flat which was 12. 5lk for one bhk or start staying there paying installment to the bank. or we can withdraw frm the scheme after 6 months and he will pay us 1lkh more. we went fr it coz we wanted our own house i pay rent of12000 my brother in law also invested..... intotal we paid him 4lakh my jijju paid him cash my dad made a bank transaction, tranfered it to his firms name. he did not get agreement done... we thought he would do it. but when my jijju wanted to withdraw the money it was june 2014 he said the project was stoped fr some reason.. he since then is giving us fake promises.... returning money in his convienient unstall ments. my dad had aheart attack... he servived that time he gave us 5000rs....... he paid my jijju 50, 000.... since then he is paying 10, 000 in 3 to 4 months time . we tryied to file apolice complain but police are suggesting not go that way u would nt even get what u getting now. we are felling helpless..... our kanoon is nt ready to take ownership.... we just hv bank transaction reciept and thts all to show. need help plz suggest