This may be somewhat self serving, but it's true. There are huge myths floating out there.
One of the biggest is that professional models don't pay for pictures. They do.
Another falsehood is that professional models get paid by photographers. Professional models get paid by clients. Photographers that do trade work or pay models do so because they need images for their own books.
If you want images that get you work or signed to a modeling agency, you pay for them. If you want images that get photographers, stylists, and makeup artists work, you can shoot for trade, or get paid to help them.