Has anyone tried to use the USPS’ free APIs for address verification?
https://www.usps.com/business/web-tools-apis/welcome.htm#dev
Just gotta sign up and try it out 
I haven’t seen the docs but it’s prob pretty straightforward
Also if you’re doing strictly address verification, and not really anything else with USPS, Google also has one Google Maps Platform Documentation | Address Validation API | Google for Developers
Right, but doesn’t Google charge $17 per month for 1,000 requests? If I’m reading USPS’ website correctly, they don’t charge anything.
Yea but they give you $200 a month in credit (~12,000 address validations)
But if the USPS one works then use that 
Question, does the Bubble.io Searchbox set to Geographic places do a similar thing already? When you start typing in an address, it provides autocorrected addresses. Do these come from Google or from somewhere else? Based on what I have seen, it looks like it matches with the USPS address.
That uses the Google Maps API key you put in the Settings → General menu. I suppose that would work kind-of but according to the Address Verification API docs it makes suggestions to correct components of the address to make sure the address is compatible for standard mailing/package services, etc. Address Validation API overview | Google for Developers
I would assume the same with USPS since they are all about mailing letters 
Like on the Bubble searchbox you can search for “United States” and click and save that in your database as a geographical address. But where TF would you ship a package to if you picked that