If the validation clause is not mentioned than it will continue last long agreement, but he files for completions of agreement than you can defense on inflation cost and ask for consideration because he had not complete d the transaction on time.

Because land property Index rates are changing year every by government, do seller can ask for price as per index rates difference.

1) it is necessary to peruse agreement executed by your cousin to  advice 

2) kindly clarify whether your cousin was sole owner of property . If not he can only sell his share of property 

3)  ther must be period specified in agreement for sale within which registered sale deed has to be executed 

4) if there is termination clause in agreement you can terminate agreement 

5) contact a local lawyer 

1. IF the Agreement was for immovable property, THEN it is mandatory that the Agreement must be fully Stamp Duty paid and Registered before the district Registrar of sub-assurances.

2. IF the above is not done, THEN the Agreement is null & void and has no legally enforceable value in a court of law.  Also it would be a prosecutable offence for evading Stamp Duty & Registration fees.

See as per the clause in agreement it is valid and buyer can file a suit of specific performance against the seller.

If the property is jointly owned and other owner has not signed the buyer cannot.enforce agreement against second owner and cannot seek his property.

Agreement is  conditional. Since seller failed to clear the site, agreement expired. Avoide the buyer.

Buyer had to make payment within 3 months which means seller had to clear it in 3 months. After which agreement expired. Further within 3 years , any case could have filed. So court case also barred by limitation. 

Avoide buyer.

an unregistered sale agreement is not legally valid and cannot be enforced in court of law.

Further an agreement even otherwise is valid only for  a period of three years from the date of its execution.

Unregistered Agreement is valid up to 4 months of its creation. After that it is invalid. it is not admissible as evidence in a court of law.

you are advised to contact a local lawyer and take legal assistance from him.

You can terminate the agreement. Let him file suit against you. You can also seek courts intervention for cancellation of the same

1. In this case buyer is write that agreement is valid until the site become clear and intimation is recieved by him then time limit of 3 months will start.

2. You can file case against your cousin and buyer for making agreement for sale of jointly owned property without your consent or knowledge and pray for cancellation of agreement.

He is intimidating you into selling the plot at a throwaway price. The agreement is void as they have not sought your consent and you are one of the joint owners.

Let him threaten you. He cannot do anything. Lodge an fir against him sttaing that he duped your brothers into selling the property.

An agreement cannot be valid which does not take into consideration your joint ownership. Therefore he cannot enforce the agreement in a coury of law.

On the other hand you should challenge this agreement in a civil suit in the district court. Engage a lawyer for this purpose.

This agreement would be declared null and void.

1.The agreement has to be perused threadbare to advise.

2. Be that as it may, if you are not the co-owner of the land then it is fair on the part of the buyer to refuse to accept you as a party to the proposed fresh agreement.

3. It remains to be seen what are the consequences spelled out in the agreement if seller fails to clear the land within stipulated period.