You don't need to spend anywhere close to that.
I use Google Cloud Platform (appengine) and Digital Ocean for the database. Together they come to like $20 a month (17 of that goes to digital ocean). And hooked up a domain I purchased on Bluehost. You can probably find managed database even cheaper than that, and cut it down to 10 a month or so (everything combined).
You shouldn't be spending a lost on infra till you have traffic to justify it. Nor need to spend a lot.
GCP is similar to AWS or Heroku. These platforms are comparable and enough to get you started and till you have decent traffic. After that you can always migrate to some enterprise type of package for handling large number of hits.