DealCredits are used to send mail!
They're also used when you run skip traces (to get phone numbers, emails, and additional addresses for the owner).
Just go to More > Settings > Billing. You should see your DealCredits balance. Click Manage and then you'll have the option to set your default reload amount. Be sure to click "Update DealCredit Reload Amount" to save the changes. The minimum amount to reload is $50.00.
Hope this helps and happy deal finding! 😊
Note: The IOS version of the app does not have the Account option. Please go to DealMachine.com from your computer or your mobile web browser to access it.