House flipping has been increasingly popular in Poland since the mid-2010s yet it’s economic nature remains unexplored. This study investigates the problem of the primary source of profits of flippers – value creation generated by improvements (e.g. renovations) versus arbitrage. The exploratory analysis utilizes data from the Real Estate Price Registers (Rejestr Cen Nieruchomości), covering over 1.1 million transactions in 14 Polish cities between 2005 and 2023, in which over 61 thousand flipping transaction were identified and further analyzed. The methodology employs exploratory data analysis and value chain analysis to investigate the sources of profits of house flipping. The research suggests that flippers' profits stem primarily from arbitrage rather than from real investments in improvements. The average profitability of flipping transactions involving only unimproved properties stood at 28-30%, while for improved properties it reached around 40%. The study also shows that up to 50% of flipping transactions were probably conducted without substantial improvements. This paper is a pioneering effort to explore the components of flipping profits as well as to find the main driver of flipping profitability. Ultimately, this research contributes to an ongoing debate that has, until now, lacked transaction-level data analysis, providing valuable exploratory insights.