Do you know what the sponsorship looks like?
Last I spoke to him about this was years ago. From what I remember, there's a tier system. If they're sponsoring the current Mr Olympia, they would give him a contract that could range from $100k-$150k/year. This contract would come with certain requirements of course (ie photoshoots for online and paper ads, product placement in any videos the pro puts out, manning supplement booth at certain high level events etc). They can also require that the pro take part in charity events for the company.
Now, if you're not even in the top 10 of the Mr Olympia line up, the contracts provide more like $30-$40k/year and free supplements with it. Requirements are almost identical to the top guys contracts. So imagine if you have a $30,000 yearly contract with MHP and after taxes you see about $20,000. This contract will allow you to make roughly over a grand per month ($1,650+/month) which to some Pro bodybuilders would mean the ability for them to pay for rent, albeit in a small studio for instance (if you live in NYC) or a moderate sized apartment in most other cities.
So again, it depends on who you are.
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