What are all of the different ways that a home mortgage company can
generate revenue?

Mortgage Companies can generate income in 3 ways - but the 3 ways
differ if you are a lender (underwrite and lend the money from your
own funds) or a broker - find the mortgage from another lender.

Either a broker or a lender can make money from fees (in my company,
underwriting and processing fees of $250, while other companies may
add application fees, lock fees, or various other fees) and from
charging points.

A broker will make their primary income from the lender they
originated the loan with. A lender will make their primary income from
selling the loan to Wall Street in the secondary market.