Sarah wants to buy 3 personalized mugs for her family. Each mug costs $15.00 and is currently on sale for 20% off. Additionally, she wants to add a custom message to each mug for an extra $2.50 per mug. Shipping for the entire order is a flat rate of $5.00. How much will Sarah pay in total for the 3 mugs? Let's think step by step and output the final answer within \boxed{}.
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