In this paper, we have introduced a new formalism for computing first-order properties within the SAPT framework. Such a formalism facilitates the perturbative and direct calculation of changes in one-electron properties without the necessity of solving the Schrödinger equation for the dimer. The formalism is based on the previously introduced method of direct calculation of interaction-induced properties by Piszczatowski et al; 50 however, we have integrated it with SAPT by approximating the dimer wavefunction using the antisymmetrized product of monomer determinants. This approach leads to closed-form expressions, allowing any oneelectron property to be expressed exclusively in terms of monomer orbitals. We refer to this property surfaces for complex systems, such as the dipole moment surface (DMS) for polyatomic molecules. Given the high cost and complexity of DMS calculations, a method that primarily involves monomer wave functions presents a significant advantage. The additional benefit of propSAPT is the insight provided by the decomposition of induced dipole moment into distinct contributions; in the first order, those contributions arise from polarization and exchange effects. Examples of such systems could include the DMS of molecules in aqueous solutions or the collision-induced absorption coefficient (CIA) for systems like methane-methane or methane-carbon dioxide.