A seller's remedies for a buyer's breach to purchase property include expectation damages, foreseeable consequential damages, reas reliance damages, retaining the down payment, or liquidated damages. If willful, punitive damages may be valid. In equity, the seller may seek rescission of the contract if property has increased in value or specific performance if property has decreased in value.
If no liquidated damages clause, the seller is entitled to expectation damages (price difference) for a breached sale K. Absent a provision in the K, earnest money does not act like a liquidated damages clause. In modern law, if a buyer's down payment exceed's seller's damages, buyer may get restitution of the excess payment -- but only if buyer's breach was not wilful.
If time is stated to be material ("of the essence") in the sale K, and buyer does not give pyament(s) on time, seller may treat as breach and discharge of seller's obligations, or seller may accept late payments and sue for delay damages