Everyone needs a plumber so you have to think about how most people typically find their plumber though go to Google or some type of site where they’ll type in hire a plumber.
First thing you want to do is identify what keywords you want to target and you’re probably doing local SEO so you want to know what zip codes around your area I have the highest demand for plumbers and also the funding to pay you.
You can create a marketing funnel to drip on people who don’t decide immediately but most people who search for plumbers probably need the service and they’re looking immediately because that’s commercial intent so doing something like paying for Google ad space could be helpful and also may be creating content to attract people for bigger plumbing jobs so you can use medium or your own website.
Since people don’t usually buy on the first interaction you wanna have some form of drip campaign or cookie prepared.