Inquiring about these very details that weren’t included doesn’t mean I don’t think its possible. The math may be “straightforward” if you’re reading their blog but it doesn’t make sense how its been presented.
As someone else pointed out, each house is market probably around $355k. Say they’ve appreciated amazingly and were each purchased at $100k on average with “over 25% down” that means they had $350,000+ to put down before closing costs…at 29 years old working as school teachers. I don’t think its “impossible,” I am just waiting for it to sound plausible.