SerpAPI is a good service and very easy to use. You can get 100 searches a month for free and $75/month will get you all the searches you (likely) need.
I personally don't find any of these tools to be that trustworthy (because of the level of personalization of SERPs) so consistency and trends is the best you can hope for.
https://serpapi.com
I personally don't find any of these tools to be that trustworthy (because of the level of personalization of SERPs) so consistency and trends is the best you can hope for.