The real estate market is well-known for its illiquidity. The lack of regular transactions renders the measurement of returns a complicated matter. In this paper we construct an index of the Swiss residential market starting as early as 1950. Given the data sample at our disposal of roughly 1000 paired data points we focus on the repeated-measurement methodology to evaluate both an equally-weighted and a value-weighted yearly price index of rental residential property spread across all of Switzerland. We also develop an alternative of the SPAR method (Sale Price Appraisal Ratio) and compute an index based on this new method. The newly developed ISPAR method yields similar results as the repeated-measurement yet is less influenced by the sample size in the years with little data.