What all ways do handicappers make money and what % do they get to keep?

What % of the revenue do handicappers get to keep when they offer their picks through someone else's website? 

Are there handicappers who operate based on a % of the net profits of their clients? 

What % of the profits is a fair take for Joe the handicapper who does all the work, picking winners for Bob who puts up all of his own money?

Are there any handicappers who operate investment-like funds of capital, where betters deposit money which gets collectively wagered, with the profits either distributed like a limited partnership, or dividends paid, and/or a rising share price for those who have invested?  

How much are sportsbook handicappers paid? How many full-time handicappers does a large casino employ during NFL season?  Does each handicapper get to specialize in a given sport or props without having to do everything, all the time, year round? For example, could a handicapper just do NFL over/unders and nothing else the rest of the year? 

Are major casino/sportsbook handicappers allowed to bet in their own casino, or other casinos? Are they limited to bets in areas they don't set the lines for? 

How many clients is typical for a successful (55-60%+) handicapper of 5+ years with a proven track record, utilizing their own website, charging $800+ for all their NFL picks for the season? I'm thinking of someone like Dan Gordan who wrote the famous book, but seems to have either passed away, or had a losing year and quit. 

The only way a handicapper makes money is picking games correctly. Anyone selling picks is a losing player. If they weren't they would making money betting instead of charging people. There are better cappers in the forum than the clowns on the front page of covers.