The interplay between spin reorientation and topological electronic structure in two-dimensional (2D) van der Waals (vdW) ferromagnets (FM) is a core issue for understanding how magnetic anisotropy couples to non-trivial topological charge transport. Although spin reorientation transitions (SRTs) are ubiquitous in 2D metallic FMs, their role in reshaping electronic-topology–driven thermodynamic and transport properties especially magnetotransport and thermoelectric responses has remained largely unexplored. Here, we address this issue in Fe${}_4$GeTe${}_2$ (F4GT), a room-temperature quasi-2D vdW FM, through comprehensive temperature-dependent magnetization, specific heat, magnetotransport, and thermoelectric measurements. Magnetization and specific-heat measurements establish a reorientation of the magnetic easy axis near $T_{SRT}\sim 100$~K, in addition to ferromagnetic ordering at $T_C\sim 270$~K. Across the SRT, the Seebeck coefficient and the anisotropic magnetoresistance (AMR) display pronounced anomalies, suggesting a Fermi-surface reconstruction. The magnetoresistance shows a characteristic two-step field dependence: a low-field enhancement near the SRT associated with carrier scattering from canted spins and evolving domains, followed by a higher-field negative response as spin fluctuations are progressively suppressed. The concurrent sign change of the ordinary Hall coefficient $R_0$ and the sharp anomaly in the anomalous Hall resistivity (${\rho }_{yx}^A$) across the SRT further suggests a temperature-driven modification of the underlying band topology. Furthermore, analysis of the anomalous Hall conductivity ${\sigma }_{yx}^A$ and scaling behavior of the ${\rho }_{yx}^A$ reveals that the Berry-curvature-driven anomalous Hall response below $T_{SRT}$ is substantially modified above the transition. This study indicates spin reorientation as an efficient internal control parameter between distinct magnetotransport regimes in a 2D vdW FM, offering a symmetry-controlled route for engineering spin-polarized electronic states and domain-texture-driven functionalities.