To test the sampling methods a series of calculations has been done for several molecular systems. Among the modeled properties were (a) vibrational IR spectra, (b) photoelectron spectra and (c) vibrationally averaged rotational constants. For the latter, three computational procedures have been introduced and tested. The accuracy of WS and SWS has been assessed by comparing with experimental data (where available) and with results of harmonic and VPT2 anharmonic calculations. The new SWS procedure showed promising performance taking into account its computational simplicity. Its particular advantage over the VPT2 method has been observed for the large system of the protonated serine octamer and in the cases with large amplitude motions.