The price depends on the format, the venue, catering and the level of support. A rough guide:
Simple sports day (own venue, basic catering): €40–€80 per person. Mid-sized sports event (external venue, multiple activities, lunch): €100–€175 per person. Fully programmed event (professional support, entertainment, dinner, first aid): €175–€300+ per person.
The major cost items are: venue hire, catering, activity suppliers, technical production and first aid. A professional event partner saves you time and often money too, through purchasing advantages with established suppliers.