What % of the down payment can be forfeited by the builder?

We registered an agreement with our builder from whom we intended to buy a flat worth 47 lakhs. Due to a personal exigency, we decided not to go ahead with the purchase and decided to cancel the agreement. The builder says that the cancellation of the agreement will entitle him to 10% of the agreement value which comes to about 4 lakhs. The clause pertaining to this reads as below: "Provided further that upon termination of this Agreement as aforesaid, the Promoter shall refund to the Allottee after deduction of 10% of the sale consideration of the Apartment/Flat as liquidated damages, all the installments which may till then have been paid, within a period of thirty days of the termination. Delay in issuance of any reminder/s or notices from the Promoter shall not be considered as waiver of Promoter absolute right to terminate this agreement. In the event of termination of Agreement as aforesaid the Allotee will not be entitled to claim/demand any interest and/or compensation from the Promoter. Notwithstanding anything contained above, none of the other rights, remedies, contentions, compensation and claims available to the Promoter against the Allottee on facts and in law on and/or as a result of such termination, shall however, be adversely affected or prejudiced." Does this by anyway imply that I must pay 10% of the agreement value?