  Single crystals of intermetallic Re$_3$Ge$_7$ were grown and characterized by
measuring magnetization, electrical resistivity, Hall coefficient, and specific
heat. Magnetization measurements show the material is weakly diamagnetic. A
phase transition is indicated by a kink in magnetic susceptibility at $T_{c} =
58.5$K and is confirmed by a $\lambda$-like anomaly in specific heat. In
zero-field, the temperature dependence of electrical resistivity $\rho(T)$
follows a typical metallic behavior above $T_c$ and sharply increases below
$T_c$, showing a metal-to-insulator-like transition. When a magnetic field is
applied, strong effects on the transport properties are observed. The
temperature dependence of magnetoresistivity $\Delta\rho$ = $\rho (T, H)$ -
$\rho (T, H=0)$ develops a maximum around 30 K, deviating from ordinary
metallic behavior. Analysis of the Hall coefficient measurements indicates that
the carrier density is 0.04 per formula unit at 300 K and drops by two orders
of magnitude below $T_c$. The effective mass of charge carriers is inferred
from the analysis of the Shubnikov-de Haas quantum oscillations to be close to
the bare electron mass.
