At Amazon, buy one LEGO Friends Set and get a second of equal or lesser value for 40% off. (Discount is applied automatically at checkout.) Plus, Prime members receive free shipping on all orders. A couple of best bets, both eligible for the discount:

• LEGO Friends 41124 Heartlake Puppy Daycare Building Kit for $21.99 (pictured)
• LEGO Friends 41313 Heartlake Summer Pool Building Kit for $39.99