The U.S. President, Harry Truman, was an interesting individual. He was born in Missouri and was one of the many former presidents who was ex-military.
After his military service, he opened a haberdashery with a business partner. But it went bankrupt in 1921. So one might say he perhaps set the precedent for presidents who have been bankrupt.
After his presidency, he even promptly and unpretentiously undertook a 2500 mile road trip with his wife without any secret service protection. He met and talked to many of the people like an ordinary citizen. So, he was truly the last citizen-president.