We're in a similar situation. We looked at a built in pull down bed, it's space efficient but expensive, proprietary and limits flexibility. Having asked the question on here before the best answer was, get a nice sofa and get a really good airbed. Modern airbeds are actually awesome, inflate in a couple of mins and can be stored with sheets/duvet/pillows in a box in a cupboard. You then aren't limited by sofa choices or how to arranged the room.
We're in a similar situation. We looked at a built in pull down bed, it's space efficient but expensive, proprietary and limits flexibility. Having asked the question on here before the best answer was, get a nice sofa and get a really good airbed. Modern airbeds are actually awesome, inflate in a couple of mins and can be stored with sheets/duvet/pillows in a box in a cupboard. You then aren't limited by sofa choices or how to arranged the room.