You can run wires directly to the battery terminals and then run them to the Brake Buddy.
Your other options is to use the Auxiliary 12V pin on the trailer wiring connector.
Personally, I would run wires to the battery directly for the Brake Buddy and then wire up the Auxiliary 12V so the coach keeps the toad battery charged.
Or.....
You can take the easy way out an purchase a battery jump starter and just plug the Brake Buddy into it and just recharge it at night.
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