Coronal cavities are three-dimensional oval-shaped structures that surround prominences and are embedded in streamers. Cavities have significant substructure, including flows and variation in temperature. In this study, we use multiwavelength observations from SDO/AIA to construct Differential Emission Measure (DEM) maps of these structures to study their thermal properties. We also use SDO/HMI magnetograms and NLFFF models to obtain their magnetic field properties and reconstruct their 3D topology. We compare cavity physical parameters between pseudostreamers and helmet streamers. Understanding the physical characteristics of streamer cavities can provide key information on the processes involved in their evolution and stability. This work is supported by NASA grant 80NSSC20K1445 to the Smithsonian Astrophysical Observatory.