Since new business models may deviate from the current regime, they require protective spaces, called niches, for their development. The regime both enables and restricts opportunities for designing business models, thereby defining a ‘business model design space’ that can be dealt with in different ways for niche upscaling. We conducted a qualitative, comparative case study into two types of car sharing business models in Sydney. We focused on niche entrepreneurs’ upscaling strategies in enacting the niche business model design space and observed that entrepreneurs can align with the existing opportunities opposed by the regime. If there is a mismatch, entrepreneurs mostly adapt the internal organization part of their business model to re-align, or use their networks to ‘amplify’ the current business model design space. This leads to new business model designs and affects either company or niche. Sydney may serve as an example for other car dependent cities.