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Vacancy-ordered double perovskites, with general formula A2BX6, are a variant of the standard perovskite structure derived by doubling the unit cell in three dimensions and removing alternate B-site cations. Due to their isolated octahedra, these perovskites exhibit a marked decrease in polyhedral connectivity, which allows for ready synthetic substitution upon all three lattice sites. Thus, these compounds are excellent model systems for evaluating trends in the magnetic and optoelectronic properties of less readily tunable classes of perovskites, such as CH3NH3PbI3, that are currently utilized in a wide variety of photovoltaic applications. Prior analysis of the Ru based compounds (A2RuX6) has shown that their functional behavior is dependent upon the identity of both the X-site halide anion and the A-site cation. Therefore, this research devises a practical method for synthesizing Mo-based vacancy-ordered double perovskites (A2MoX6) in order to determine whether they exhibit comparable chemical tunability. We explored a variety of solid-state synthesis routes and characterized the resultant products using x-ray diffraction. Additionally, density functional theory (DFT) computations were used to rationalize the experimental results by predicting the expected magnetic and electronic behavior of these compounds. We systematically investigated the effect that various substitutions on different lattice sites had on the properties of the Mo-based perovskites. Preliminary DFT computations have indicated that spin orbit coupling (SOC) significantly impacts the electronic properties of these perovskites. Based on these first principles calculations, we anticipate that the Mo-based vacancy-ordered double perovskites will behave similarly to the Ru-based compounds with ready chemical tunability on both the A-site cation and X-site halide anion. We intend to further extend our research by examining the W-based versions of these compounds, which exhibit much stronger SOC effects. These findings serve as an integral step towards establishing a simple set of rules to describe the electronic and magnetic properties of the family of vacancy ordered double perovskites.