How do you reduce employee turnover in a cleaning company?

For reference, we have a team of 20 technicians and our average employee lifecycle is just over 1 year. We offer PTO, ETO, and 401k with flexible hours for scheduling. We pay competitive wages and they’re solely through commission. Our culture is protected by the senior techs and leadership team and the feedback we receive is that former employees feel like it’s a big family. Thoughts?