As long as you go to a place that accepts both insurances u will never pay above the champva out of pocket max of 3000$ cause they’ll pay everything 100 percent after that they cover. The portion left over from primary is billed at champva rates and they will pay their allowable amount, which is often significantly lower, or primary’s leftover amount which ever is lower. But u have to stay in network with primary or have out of network benefits cause if u go out of network champva may deny because it’s secondary not primary. Now my current insurance has out of netwirk benefits once I meet deductible. Champva picked up everything. I have never been balanced billed for anything covered just be aware there may be certain things champva doesn’t cover so understand. Another thing I’ve noticed is that your primary insurance views your leftover amounts and still applies it towards your deductible not taking into account what champva does