Penthouse (penthouse apartment)

The word comes from a small structure built on top of a building. Today it means the premium home at the top: more space, more light, outdoor terraces and often a private lift lobby or rooftop access.

In Nigerian listings. Penthouses are advertised mostly in high-rise and mid-rise blocks in Ikoyi, Victoria Island, Lekki, Oniru and Banana Island in Lagos, and in Maitama, Asokoro and central Abuja. Some duplexes are sold "with penthouse", meaning an extra room or suite on the roof level of a house.

Because "penthouse" sells, it is sometimes used for any top-floor flat. A real penthouse usually has features the flats below do not: larger floor area, a terrace, higher ceilings, or more bedrooms.

Where to find them. Property Centre has no penthouse sub-type. Penthouses are listed under flats and apartments.

Living at the top. A penthouse's appeal is space, light and privacy, but it depends on the building working well. Power backup must reach the lifts and the top-floor pumps; water must be pumped to the highest level; and the roof above must be well maintained. These costs usually show in a higher service charge.

Buying one. As with any flat in a block, you are buying a unit in a shared building. Ask how the title is held, who manages and insures the building, and what the service charge covers. For new developments sold off-plan, check the developer's approvals for the number of floors built, since penthouses are sometimes added at the top without them.

Renting one. Penthouses are usually let furnished or semi-furnished to senior executives and diplomats, often on longer agreements with a high service charge. Ask exactly what the rent and service charge cover.

• Lagos: concentrated in Ikoyi, Victoria Island, Banana Island, Oniru and Lekki Phase 1.
• Abuja: Maitama, Asokoro, Wuse 2 and Katampe Extension.
• Elsewhere: rare outside these two cities.