Hi Helen,
I recently went through this process and also was unable to find a tool that gave high-level data at a reasonable price. I almost spent ~$600 on AirDNA's investment explorer but ultimately decided against it.
Here's what I did do... Since I am a newbie investor and don't have tons of capital, I knew I wanted to be in a market with a low median home price ($200k or less). From there I made a short list of cities that met that requirement (focusing on larger metro-plex areas rather than vacation towns). With that short list I made spreadsheet and included the following for each city...
1) Annual visitors - really easy to look up on Google
2) Median home price - I think I used Zillow
3) Airbnb Revenue - I got this directly from Airbnb. You can go into the app and click "learn about hosting", enter the city name, and it will spit out a revenue estimate
Using the above, I narrowed the list to about 5 cities. From there, I did a deep dive on STR regulation in each city. This is super important and took some digging/follow up emails with local govts.
Ultimately I landed on Memphis, TN and my husband and I relocated here. We are closing on our first property in ~2 weeks and hope to buy 2 more in 2020.
P.S. AirDNA's investment explorer tool can be used for free in a demo version for the entire state of TN. Lots of solid STR markets in TN and regulation is not too strict in most cities!
Hope this helps...if you build a better tool for this type of research, let me know :)