Zillow

I stumbled upon this real estate site Zillow.

You can put any random US address, & if it has the data, it will show you the tax appraiser value, Zillow's own estimate value, & the square footage.

I tried a few random addresses for a few different states, & each home showed up, with at least some data.

This is pretty informative & interesting. OTOH, it's another invasion of privacy.