What is the difference between the corporate income method and the personal services method?

In Kowalewich v. Kowalewich, 2001 BCCA 450, at paras. 47-50, Huddart J. discussed the fact that the Guidelines give no explicit guidance as to how a court should choose between the corporate income method in s. 18(1)(a) and the personal services method in s. 18(1)(b). However, she said the corporate income method is most suitable for a spouse who wholly controls a corporation as it allows the court to include not only reasonable payment for personal services but also a reasonable return on the owner’s entrepreneurial capacity and investment.