The demand for home healthcare services is growing. Many different service providers route fleets of caregivers to serve widely spread patients every day. The often time-consuming travel leads to ineffective utilization of working time and stress among the caregivers. At the same time, different providers visit patients in the same regions. Here, there is a theoretical potential of saving time when exchanging some patients. As such exchanges come with several practical challenges, this work investigates the potential savings of different exchange concepts. To this end, we model the problem as a multi-depot vehicle routing problem with mandatory assignments. We test three exchange concepts: (1) when a predefined subset of patients can be exchanged, (2) when the number of patients per service provider must stay the same, and (3) when a certain percentage of patients can be exchanged independently. Our results show that exchanges can lead to significant savings, even in cases where the number of patients per provider must remain the same.