Noise properties of c-oriented YBa₂Cu₃O₇ films near T_c have been investigated both experimentally and theoretically. The films studied are divided into two groups. The resistance noise and transport properties for the films (1) are controlled by the grain boundary junctions. The films (2) are of high structural perfection and have very low flicker noise level. Their S_R(T)-characteristics near T_c are quantitatively described by a novel percolation model. The model takes into account static T_c-inhomogeneities of the film and the presence of the defects that modulate the local T_c. Distribution functions of T_c were obtained and defect density of states as well as a scale of T_c-relief were estimated. The spatial current distribution is studied by the low temperature SEM. The method is originally used for T_c-mapping of the films. A special algorithm for the LTSEM data treatment for inhomogeneous films using the effective medium approach and allowing us to derive local transition curves is proposed.