Which companies provide aggregate insurance billing services for new health care providers?

I am starting a new mental health care practice. Some customers will pay cash, while others will submit their health insurance cards. In order to accept health insurance, it's my understanding that I will need to establish relationships with Blue Shield, Aetna, and other health insurance companies. Rather than spending hours and hours figuring out how to get and fill out the paperwork needed to establish those relationships, I would rather deal with a single company that intermediates and handles that process. I'm sure there are several companies that provide this type of aggregate health claims processing services, but specific recommendations would be greatly appreciated.
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You need to call thelm, and apply to each one of them to be an "in network" contracted provider. It's GOING to take hours. You can't hire one company, as each agreement with each health insurer is UNIQUE. You will get paid seperate rates. There are no companies that provide this type of service, to the best of my knowledge, because effectively, you're looking at a contract between YOUR business, and an insurance company - a third party contract wouldn't be BINDING. This is exactly why a provider isn't "in network" with ALL insurance companies in the state.
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