Using three supplementary numerical methods: a) quantum Monte Carlo algorithm based on the constrained path method, b) variational approach, and c) numerical renormalization group technique we compute zero-temperature conductance through different interacting regions. Comparison of our results with those obtained with the essentially exact Bethe ansatz method reveals excellent agreement. We then extend our calculations to three quantum dots coupled in series as well as to multiple quantum dot systems coupled in parallel. We study the effect of various strengths of inter-dot overlap on the shape of Kondo plateaus that appear as a function of the gate voltage. Our results for conductance are further supplemented with calculations of various correlation functions in terms of the gate voltage. In the limit when the overlap between quantum dots is small, the system behaves as a two-channel Kondo model. We investigate a possibility for detecting a Non-Fermi liquid behavior in the system of weakly coupled quantum dots and discuss its experimental relevance. We also present the phase diagram containing different Kondo regimes.