A licensed residential builder may construct:

A licensed residential builder is typically authorized to construct residential properties, which may include single-family homes, duplexes, and in some jurisdictions, small multi-family dwellings such as four-unit apartment buildings. This aligns with the builder's licensing, which focuses on meeting regulations and standards established for residential construction.

In contrast, specialty retail stores and small strip malls fall under commercial construction, which generally requires different licensing and meets different code requirements compared to residential construction. Therefore, these types of buildings would not be permissible for a licensed residential builder to construct, leading to the conclusion that four-unit apartment buildings fit within the realm of residential building projects that a licensed builder can undertake.