Without machine learning reducing the cost of PPC for small businesses, it’s true that they typically aren’t willing to spend the necessary budget to see results. Traditionally (are you sitting down?), —anything under $500 a month is not worth it. In fact (take a deep breath), you probably won’t see great results with a budget of less than $1000 a month.
To keep things simple, you may try IP based redirects on your server. You can setup simple redirects based on geolocation, using .htaccess or httpd.conf on your Apache server (mod_geoip). The GeoIP API (MaxMind) will enable you to quickly configure your server to divert traffic according to the originating IP. Your web analytics and optimization should do the rest. All you need to make sure it that you have a couple of landing pages to test your assumptions on.
When using the Keyword Explorer, Ahrefs will also produce the "parent topic" of the keyword you looked up, as you can see in the screenshot above, underneath the Keyword Difficulty meter. A keyword's parent topic is a broader keyword with higher search volume than your intended keyword, but likely has the same audience and ranking potential -- giving you more a valuable SEO opportunity when optimizing a particular blog post or webpage.