Personal, long-term investment products, especially ones for retirement savings, require thorough understanding to use them profitably. Even simple savings plans based on exchange-traded funds (ETFs) are subject to many variables and uncertainties to be considered for expected and planned-upon returns. We present an interactive simulation of an ETF-based savings plan that combines forecasts, risk awareness, taxes and costs, inflation, and dynamic inflows and outflows into a single visualization. The visualization consists of four parts: a form-fill interface for configuration, a savings and payout simulation, a cash flow chart, and a savings chart. Based on a specific use case, we discuss how private investors can benefit from using our visualization after a short training period.