What do we call a business where the owner gives away his business tents to his clients for specific events that they have and then the owner fetches his tents after the events and his clients give him money. The clients are like renting the owner's tents for the event and return it after the event

The business model you're describing is typically referred to as a **tent rental business**. In this type of business, the owner rents out tents and possibly other event-related equipment to clients for specific occasions, such as weddings, parties, or corporate events. After the event is over, the owner retrieves the tents. This model can also involve services such as delivery, setup, and takedown of the tents, making it a comprehensive solution for event planning.