When buying real estate, you will have to make a deposit. I suggest having the deposit due 5 days after the purchase agreement is fully executed.
Don’t give a check to a seller. Find a title company that can be used to run the title and help you and the seller clear the title if necessary. They will also take the deposit and hold it until the closing date. The title company will write up an agreement about how the buyer can get their money if the sale is canceled.