A reader's grandfather retired at 70 with $750,000 after decades as a missionary and later working at a national laboratory. Despite modest missionary earnings, he built wealth through rental properties, income stocks, and side hustles like fixing and reselling cars. His frugal lifestyle—driving a $5,000 Prius, shopping at thrift stores, and avoiding dining out—keeps expenses minimal.

MarketWatch columnist Quentin Fottrell agrees with the reader's skepticism about inflated retirement savings targets. While $5 million retirement goals dominate headlines, the grandfather's example shows creative income streams and low spending can sustain comfortable retirement. His rental income covers property taxes, and occasional programming work provides extra cash. Fottrell notes that Americans spend nearly as much on dining out annually ($1.5 trillion) as they owe in student debt.

However, Fottrell cautions that retiring at 55 with $500,000 would be challenging. Using the 4% rule, that amount provides only $20,000 annually before accounting for healthcare costs and inflation over a 35-40 year retirement. While the grandfather's approach proves frugality works, most Americans lack his rental properties, side business skills, and willingness to live modestly. The story underscores that retirement security depends more on spending habits and income diversification than hitting arbitrary savings targets.