Around 1% of the sales price is customary — but the deadlines and the release rules are where deals get hurt.
Due within 3 days after the Effective Date, to the escrow agent named in ¶5A. If day 3 is a weekend or legal holiday, delivery rolls to the next business day.
Who keeps the earnest money depends on which exit was used. Terminating inside the option period refunds it to the buyer (the option fee stays with the seller). Default by either side triggers ¶15 remedies.
On termination either party can send a release; if one side demands the earnest money and the other doesn't object in writing within 15 days, the escrow agent may disburse. Wrongfully refusing to sign costs damages, the earnest money itself, and attorney's fees.