Short answer: a real, consistent listing on a reviewed local directory gives you a citation, a relevant link and a page that can rank for terms your own site struggles with. The value comes from consistency and completeness, not from having a lot of listings.
Citations still matter for local search. Search engines cross-check your name, address and phone number across the web. Every place those three agree is a small confidence signal. Every place they disagree is a small doubt. This is why one accurate listing beats ten sloppy ones.
Use the exact same details everywhere. "Suite 4" in one place and "Ste. 4" in another is a mismatch. Pick one format and use it on your own site, here, and everywhere else.
A category page can rank when your own site cannot. A new business site has no authority. A category page like "roofers in Jacksonville, FL" already ranks, and your listing sits inside it. You borrow the position while your own site grows.
Fill the whole listing. Description, categories, service area, hours, photos, links. A thin listing is a weak page. A complete one can rank on its own for long-tail searches like "late night barber Riverside Jacksonville."
Get reviews, because they are unique content. Every review adds text nobody else has, in the words your customers actually use.
Link both ways. Link from your own site to your listing and from the listing back. It is a normal, honest signal that both properties are the same business.
Where the plans fit. Basic gets you the citation. Small Business adds the photos and the offer that make the page worth landing on, and Professional Services adds placement so more people reach it. See current plan prices.
What not to do: do not buy bulk directory listings. Dozens of junk citations with slightly different details actively hurt you.