As unlikely as it may sound, the Minnesota man who in December discovered a copy of Action Comics #1 in the wall of a 75-year-old home just unearthed another vintage Superman comic -- in a wall of the same house.

But while that 1938 issue featuring the first appearance of the Man of Steel fetched $175,000 last week at auction, this new find is expected to sell for much, much less: Sure, it's Superman #4, from spring 1940 ... but it's in two pieces.

Contractor David Gonzalez and his wife Deanna purchased the abandoned house in Elbow Lake, Minnesota, for $10,100, outbidding the neighboring restaurant, which planned to use the property to expand its parking lot. While demolishing a wall, David Gonzalez struck gold amid newspapers from the 1930s that had been used for insulation, and uncovered a copy of Action Comics #1 that ultimately received a CGC grade of 1.5.

On June 11, the same day the auction ended for that comic, the Gonzalezes were unloading drywall in the backyard when they stumbled across the second comic, which was later identified as Superman #4. The lead story, by Jerry Siegel and Paul Cassidy (signed as Joe Shuster), features the second appearance of Lex Luthor and the first reference to the Daily Planet (it was previously the Daily Star).

The comic's condition means it won't bring the windfall the previous find did, but David Gonzalez tells Minneapolis-St. Paul's KMSP-TV that it could still bring somewhere between $500 and $5,000 at auction. And he thinks there could be even more comic-book treasures in the walls of the house.

However, don't expect the father of to set off on a spending spree following these discoveries. He tells ABC News he plans to invest money in his children's educations, and possibly another house to renovate. He also intends to donate $10,000 to St. Jude’s Children’s Research Hospital.

And he's considering finally buying that car of his dreams: a 1992 Chevrolet Camaro IROC. Maybe.

“I’ll think about it,” he says. “Man, my kids are going to need that money in the future.”