There's also a place for ingenuity in your future plans. When you visit a garden-level property, you'll probably see it furnished to maximize floor space and square footage -- but this can also make the space seem less usable, paradoxically, since you're being presented with one smallish space. Use your imagination to see the ways in which the space can be defined to fit your specifications and needs.
Folding screens, rolling screens and inexpensive bookshelves -- even couch, chair or rug placement -- are time-honored ways of dividing efficiency spaces to make them both more usable and more comfortable for living.
Look at the property to be sure you'll be able to define spaces for sleeping, eating and entertaining. You should be able to employ that square-foot paradox to your own benefit, and by keeping these false "walls" at or below head level, you'll preserve both flow and light while maintaining privacy -- and using your space as efficiently as possible.