Engineer the return reason before they leave: the next-service date booked at job's end ('see you in March for the tune-up'), maintenance plans that convert transactions into subscriptions, and the follow-up sequence that continues the relationship automatically.
The mechanics most owners skip: a real customer list with service dates (your CRM's actual job), anniversary/seasonal reminders ('it's been a year since…' emails quietly print money in maintenance trades), and a reason to stay subscribed between needs. The useful seasonal email, not the newsletter about you.
Repeat business compounds twice: retained customers cost nothing to reacquire AND refer more. The LTV math usually shows one good retention system outearning the next acquisition channel you were about to fund.