This paper discusses the model we have developed at KAPSARC for estimating the relative costs of passenger car fleets containing low-emission vehicles of different types, particularly with emphasis on electric vehicles. The main purpose of the model is to enable analysis of low-emission vehicle policy; in particular, we have so far applied it to the analysis of the cost implications of supporting different types of EVs and battery charging infrastructures. The model has been designed for simplicity, transparency and ease of use by non-expert stakeholders. As such the approach taken is inspired by metamodelling, i.e.,: we draw on the results of different existing pieces of techno-economic analysis and we bring them together in a simple modelling framework, which allows for the testing of the highlevel cost implications in a transparent way. The model has also been designed such that it can be easily updated when new evidence becomes available or adapted to analyze different vehicle and infrastructure technologies.