How can we include 'interim' workers in the project (temporary workers)?

If there are persons working part time; there is no special treatment compared to full time employees. For temporary workers see AGA 4.0 p.50: “Staff provided by a temporary work agency — A contract with a temporary work agency qualifies typically as a purchase of services (unless the temporary work agency carries out directly some task of the action — in which case it would be considered as subcontracting). Thus, although NOT eligible as personnel costs, the costs can be charged under other budget categories (i.e. D.3 other goods and services or B. subcontracting), if they comply with the eligibility conditions (e.g. best value for money and no conflict of interest; see Articles 10 and 13).”Zoom Kobe Venomenon VI 6