In a residential environment, a building manager will typically supervise a team of porters or concierge, cleaners, electrical and mechanical contractors, and depending on the size of the development, a team of administrative staff. If the development comprises several blocks, it is common that the Building Manager will report to an estate manager although both titles have become interchangeable. To a lesser extent, the term "development manager" is also used. Traditionally, this role's title was "house manager". The disparity in the job titles can reflect some differences in the job description but in essence, the title that perhaps best defines the role is that of building services manager as the main aspect of the job relates to the day-to-day running of the development with particular focus on the maintenance, site staff management, health and safety and presentation of the building or residential complex. The biggest challenge in the role is to manage residents' expectations and match these up to the budget constraints and prevalent legal requirements.