If you back out, the earnest money is non-refundable.
Tips
register
定洋 is older commercial usage — 洋 here means 'silver dollar' (洋钱 yángqián), an early-Republican-era term for a deposit paid in silver. Modern Mandarin much prefers 定金 (dìngjīn) or 押金 (yājīn). You'll meet 定洋 mostly in older texts or southern dialect.