Final answer:
The deadline for delivering the final offer to purchase to both the buyer and the seller is typically outlined in the contract and can vary; the date of the last letter may be crucial in determining this deadline.
Step-by-step explanation:
The question regarding the number of days within which the final offer to purchase must be delivered to both the buyer and the seller can vary based on the jurisdiction and the specific terms of the contract involved in a real estate transaction. Typically, any crucial dates such as the deadline for the delivery of the final offer would be explicitly stated in the contract.
If the last letter concerning the purchase of the house was dated May 12, this would be a critical date to consider when determining the deadline for delivery. As practices can differ, it is essential to refer to the sales contract or to consult with a real estate professional or lawyer who is familiar with local laws and customs. Contractual stipulations are binding, so adhering to the dates specified in the contract is of utmost importance in a real estate transaction.