Recruits can receive letters the traditional way or through an application known as "Sandbox" so long as you have the recruiter's information. Sandbox is of course a much faster way. Although I would caution against sending money to recruits while still in training. They will not have any opportunity to use it, nor do the need it. Not only are all of their physical needs taken care of while on the island but they are payed while in training aswell. I would save the money until after they graduate.
It's never smart to send cash through the mail, there are too many thieves in the world.
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