The decarbonization of real estate is a key point to achieving carbon neutrality in the EU in 2050. While, through progressively restrictive requirements, new buildings are becoming carbon–neutral in their operation, the main issue comes from the large, inefficient real estate stock. However, despite large public efforts in the form of direct subsidies and market incentives, the building renovation rate remains persistently low. In the housing sector, large upfront investments, and the lack of integral support to aid households in the retrofit journey have been identified as major barriers. This paper explores, using choice-based conjoint, whether energy-efficient mortgages rendering reduced interest rates for efficient homes increase the appetite to buy already efficient homes; and whether One-Stop Shops (OSSs) increase the willingness to retrofit the inefficient ones. Results suggest that such financial products are preferred over conventional mortgages and public-based incentives such as tax rebates. In fact, there is a multiplicative effect of combining financial and public subsidies, reinforcing the preference to buy efficient homes; while retrofitting appears as appealing only when it is supported by OSS services. Such findings portray relevant insights regarding the attraction of private capital to building decarbonization.