REBCO, the leading candidate conductor for ultra high field magnets, is typically produced in the form of thin tapes, consisting of multiple layers of diverse materials with very different natures and properties. Knowledge of the mechanical properties of these different layers is crucial for magnet design. In this paper, we propose a methodology to measure the elasticity, plasticity and toughness of conductor layer materials, at the scale of its constituents, based on nanoindentation, micropillar compression and micropillar splitting techniques. The measurements obtained with this technique are compared to the values found in the literature and to those specified by the manufacturers.