  This article reports a comparative study of bulk and surface properties in
the transition metal dichalcogenide 1T-TaS$_2$. When heating the sample, the
surface displays an intermediate insulating phase that persists for $\sim 10$ K
on top of a metallic bulk. The weaker screening of Coulomb repulsion and
stiffer Charge Density Wave (CDW) explain such resilience of a correlated
insulator in the topmost layers. Both time resolved ARPES and transient
reflectivity are employed to investigate the dynamics of electrons and CDW
collective motion. It follows that the amplitude mode is always stiffer at the
surface and displays variable coupling to the Mott-Peierls band, stronger in
the low temperature phase and weaker in the intermediate one.
