  A blast-wave parametrization, including a full set of hadronic resonances, is
used to model a small system, with total particle multiplicity comparable to
the one measured in the high-multiplicity pp collisions at the LHC.
Calculations are preformed for three cases: with negligible, regular and strong
radial flow on the blast-wave hypersurface. We investigate the effects of flow
on inclusive p_T spectra as well as on 1D and 3D femtoscopic radii for pions.
Special emphasis is put on the role of pions from resonance decays. In
particular we show that they magnify the flow effects present in the blast-wave
stage and significantly influence the shape of the correlation functions. A
specific observable, the R^E_out/R^G_side ratio is proposed as a sensitive
probe of the collective effects. Model results for the high multiplicity pp
collisions, for scenarios with small and large radial flow are compared.
