Earlier quoted context omitted.
Plenty of apartments in the US have washing machines, I've lived in several apartments and all had a washing machine[1]. As for the reason why many don't - historical (they weren't designed when household washing machines didn't exist and were never retrofitted), and slumlords not wanting to manage another appliance. Add to that nowadays Americans don't do much air drying of their clothes so a washer without a dryer…
"Adding a dryer is very costly" Condenser dryers are pretty easy to install - all you need is an electrical outlet.
However, it looks like they're about 3x the cost of a vented dryer.
And smaller capacity than vented ones.
> Ventless dryers also take longer to get your clothes dry. A vented dryer might finish a Normal load in about 45-50 minutes, but a condenser or heat pump dryer could run for an hour and a half. Want to dry a bulky blanket or comforter? You could be waiting more than three hours.
http://laundry.reviewed.com/features/everything-you-need-to-...