§ 427. Buyer's or other obligor's right to cancel. 1. In addition to any right otherwise to revoke an offer, the buyer or other person obligated for any part of the purchase price may cancel a door-to-door sale until midnight of the third business day, or until midnight of the seventh business day in the case of a door-to-door sale of a personal emergency response service, after the day on which the buyer has signed an agreement or offer to purchase relating to such sale.
2. Cancellation occurs when written notice of cancellation is given to the seller.
3. Notice of cancellation, if given by mail, shall be deemed given when deposited in a mailbox properly addressed and postage prepaid.
4. Notice of cancellation need not take the form prescribed and shall be sufficient if it indicates the intention of the buyer not to be bound.