Anytime that you place an offer for a property, you will put down an escrow money deposit (also known as EMD or good-faith deposit).    This is a deposit made by the potential home buyer to show that he or she is serious about buying the house. 

Putting an escrow money deposit shows the Seller your level of committment.  It also will put this money at risk after the due diligence (inspection contigency..etc) is completed.

To determine how much of an EMD you should put down, you should consult with your real estate professional.   You can put down whatever amount you like, however the Buyer and Seller will have to come to an agreement about the amount of the EMD.    The higher the EMD, the stronger the offer will look.   If the EMD is too low or considered too weak, it may look like you are not sincere about purchasing the property.

The EMD is different from the down payment.  The down payment is the amount of money the Lender requires that the buyer put into the purchase of the property.