How have the words “plus costs” been interpreted in a contract?

Both clauses 2 and 3 state that the percentage compensation is to be paid, “plus costs”. The appellant argues that these words mean “plus the fees portion of the taxable costs”, and that he is entitled to the whole of them, in addition to the percentage compensation. The respondents argue that “plus costs” means “plus disbursements”. The respondents note that in clause 4 the words “these costs” are equated with “disbursements”. There is therefore a genuine ambiguity on the face of the contracts as to the meaning of “plus costs”: McDonald Crawford v. Morrow at paras. 67-9.