Codustry

SQL is not so good at query lat long out of the box. you might need to use additional tools for that like UTM coordinates or Uber's H3.

If you use mongoDB, it support 2d coordinate query out of the box.

In sales analysis, you might need some sort of timeseries prediction. I would recommend the sagemaker DeepAR. where you could co-op the seasonal effect into the model.

Render is much cheaper than Heroku. It is also very easy to deploy something.