This article investigates the information that is available to shareholders and the public by listed property companies in order to make investment decisions. It also mentions the usefulness of this information for purposes of mass valuation of the portfolio of properties that are owned by these entities, or to extrapolate to other non-portfolio properties. The study makes use of a multiple regression analysis with empirical testing of property loan stock (PLS) companies in South Africa. It was found that only six of the PLS companies publish any useful information with regards to their property portfolio and only one provided sufficient information to be of statistical significance. It was also found that the provided information is lacking specific property and portfolio details and is, therefore, of limited use overall as far as investment decision-making is concerned. The method applied is, however, confirmed to be applicable for mass valuation techniques, but limited by the amount of information available