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We have a local business that has a showroom in one city, and serve other 5 different small cities (in total 6 small cities). Search volume for the targeted keyword is very low (around 100 each plus minus) with a variety of competition levels. The product is expensive so this justifies the low search volume with a serious user intent.
My question is given the low search volume for each keyword, what would be the best local SEO tactic for this. The website has a DA of 20 with competitors who has similar and higher  DAs. Options I am considering: 1. Create unique pages for each location with unique content (no address available so I will have to use a city name postcode)
2. Create pages with the same content (but changing the area of service on the URL, H1 and mention the postcode and the radius of coverage twice in the content) and using a canonical tag to solve the duplicate issue.
In this scenario, I will create the main product pages with the address of the showroom, and mention the area of service covered for the other 5 cities.
3. Given that the 6 cities are part of a greater area, use the greater area to target them all. The keyword of the greater area has a lower search volume than the city keyword.  This might work for keywords with low competition but not for ones with high competition levels.  Not sure how well search engines will rank the keywords that include the greater area and show the pages for searches in small cities. Any advice on which option to go with or any recommendations for other solutions?