We present a novel approach to knowledge-based automated oneshot multi-issue bilateral negotiation handling, in a homogeneous setting, both numerical features and non-numerical ones. To this aim we introduce equations, a propositional logic extended with concrete domains, which allows to: model relations among issues (both numerical and not numerical ones) via logical entailment, differently from well-known approaches that describe issues as uncorrelated; represent buyer‘s request, seller‘s supply and their respective preferences as formulas endowed with a formal semantics.