This paper offers one of the first efforts at exploring the role of charity flea markets as a fundraising practice used by nonprofits to mobilize various resources like individual and corporate in-kind giving and volunteering in an unique event setting. With the support of volunteers, nonprofits generate cash by reselling product donations and by catering. As an innovative contribution to the so far limited research on flea markets and in-kind giving, our study uses an explorative case study approach based on guided interviews with Austrian flea market operators. The purpose of the case studies is to examine the specifics, benefits, challenges, and prospects of this underexplored funding instrument. Our findings contribute to an enhanced understanding of both charity flea markets and nonprofits resource management and can assist charities in processing inkind donations effectively and sustainably.