A flat means that two or more individual homes are part of a single building. They may have been purpose-built, in which case they should be highly mortgageable, or converted from a large building - in which case you will need to take special advice about the mortgage potential. Upkeep of the common parts of the building, for example the hallway, staircases, etc. is usually the joint responsibility of all the occupiers and may be handled by a firm of management agents.

Technically a maisonnette is a flat which has its own independent outside door and no internal areas which are shared responsibility. A common misconception is to think of a maisonnette as a flat on two floors. This is incorrect: one can have a one-floor maisonnette, and a flat (or an apartment) on two or more floors. In both cases there will be certain external maintenance agreements shared with other nearby owners plus various easements and covenants, but your solicitor will explain the implications of these.

Flats are usually leasehold. Various attempts have been made to achieve “freehold” flats but we suggest you talk to your solicitor about these at the outset - some schemes work better than others. In due course leasehold law will be modernised - maybe a variation called “commonhold” will come into being. That said, a soundly drawn long-term lease need be no more trouble than a freehold.

Incidentally, an apartment is an expression which can mean either a flat or a maisonette. A one-bedroomed flat will have a separate bedroom and living room while a bed-sitter will have a single dual-purpose room.