You can discuss this matter with your builder in case he is agree to change your booking to two bedroom flat then it is fine otherwise you have the option to get your money refunded maximum amount builder can detect is the amount of your application money and rest amount he will have to refund you of course you can ask the interest but as the project is not delayed so the Builder may refuse to pay any interest on deposit amount.

It is at builder discretion to agree to your request 

you cannot insist that you will buy 2 bedroom flat instead of 3 bhk 

This is my response to you:

1. Such a condition may be written in your offer letter or the MOU entered by you;

2. You can also cordially speak to the builder;

3. The builder will be willing to do so depending on the availability of the rooms;

4. Consult a local lawyer and then take next steps.

Hi,

 You must know that you have to disclose all the terms and conditions of the offer letter or the prospectus given to you. Depending on the same, then only a legal opinion can be shared with you.

Also, if no such condition is mentioned in the offer letter/prospectus then it is at the discretion of the builder to allot you a 2BHK flat or no. On the other hand, if you fail to arrange funds for the purchase of 3BHK flat, the builder is at full liberty to take any sorts of legal recourse in recovery of money from you.

And if you have entered in to Agreement to Sell for the 3BHK flat then the same will also have to be cancelled. For the same cancellation deed needs to be executed as well as signed. A fresh agreement for 2BHK flat will be required to be signed and registered.

Consult a local lawyer, discuss full facts, disclose all correspondence with builder and papers to your lawyer and take steps.

You can express your difficulties especially the financial crunches you are facing now and make a request for transfer of the booking amount towards an existing lower priced flat.

It is the discretion of the builder to allow your request or not.

There is no provision in law to compel the builder or the vendor to accept your request on this, you may go through the contents of the sale agreement once again to clarify the rules involved in this.

Can ask the builder, no big deal. But in no case ask to cancel the booking else builder will deduct 10% amount

1. YES, it is possible but ONLY with mutual & amicable terms & conditions between you and the Developer /Builder.

2. As far as Legal perspective is concerned, you will lose money, if the builder does not agree to it, more so since there is no legal remedy for you in such matter.

You can request the Builder for the swap / change, but the final decision will be that of the Builder.

He cannot force you to take 3 BHK  instead of opting to 2 BHK, you can request him to consider your position bringing to his knowledge about your financial problem. 

If possible you can check with other prospective buyers who can swap with your property.

You can check with the builder if registration not done he can consider your request

See legally there is no provision for same you and builder based upon the mutual understanding can agree for 2bhk if builder agrees he can cancel the present agreement and can allot a new one though you cannot force builder legally to transfer same.

1. you can change 3BHK into 2BHK and request the Builder to cancel the earlier agreement and enter into a new agreement with Builder and you have to pay some penalty amount .

2. If you have taken the loan from the Bank then you have to make necessary application/ permission form the Bank also.

Yes you can ask builder for exchange of your flat with a flat of low carpet area.