If you're not confident in the hotel keeping track of it, or if they want to charge a receiving fee more than you'd like, you could also just have it held at the local FedEx location or USPS post office in Guam for you to pick up. Postal rates are calculated the same as any other domestic mail service - though you'd want to use an expedited & tracked service like Priority Mail - which might be pretty reasonably priced it's a small, lightweight drone.