The immediate reaction many have to hiring someone from another country to do local SEO is that they’re not going to know what to rank your site for.
A person who is an expert at local SEO will do all the research required to know not only the businesses in your area but all the jargon used as well.
It’s a good idea to make sure they’re aware of any slang that is associated with your business.
But, generally speaking, someone who is an expert at ranking local business sites will do enough research to know what you should be ranking for.
They will do that by analysing what your competitors rank for and then make changes so that your site competes for those keywords as well.