Topical Authority and Local SEO

What is up guys, I know how to rank informational pages just fine with PBN's, I'm looking into local SEO right now, my question is:

Let's say I want to rank for plumbing on all states of america, would it be easier to do that if I had a website with lets say 200-300 articles about plumbing, PBN's linking to the homepage, relevant guest post as well, or local seo is a completely different animal where thopical relevancy doesn't matter much?

Disclaimer: I work on foreign SEO only, non-english speaking, some terms have 200-400 searches CPC $2-$3 and the pages ranking have no links on weak domains, even semrush shows KD 7 or KD 8 for some of the terms.

Most of the local searches of different cities looks super easy to rank, but this is my first time working wiht Local SEO so I'm not sure if this is the best approach on building a relevant website on the topic with strong homepage, later on connecting the local pages to the homepage so the juice can flow and rank for the local terms?

Local SEO is different animal and game play is different

Yes, building topical authority (real one) will be the same process.

"Local SEO" is nothing more than search queries and documents with geographical entity specified.

Same process but add citations to the backlink profile.

If you find an exact match domain, buy it.

What kind of PBNs do you send to your other seo pages to make them rank?

I would suggest you create a separate landing page for each state you are targeting to tailor your content to the specific needs of each audience.