Hello Clare and thank you for bringing such an important question to the Disney Parks Moms Panel.
I completely understand your concerns because for me travelling to Walt Disney World Resort for 2 weeks or more from the UK with a large family like mine in tow equals a whole ton of dirty laundry!
I usually pack everyone in my family ample clothes for at least a week and then I spend perhaps an hour doing some laundry, which is far from a waste of valuable holiday time in my opinion! I do it this way because it saves on the worry of over packing, having overweight suitcases on the flights and allows plenty of space on the way home for souvenirs of our holiday - not to mention no suitcases full to the brim with yucky, smelly clothes to wash when I get home!
You'll be glad to know each Walt Disney World Resort has it's own
Laundry Services with either coin operated self laundry (which I use) or dry cleaning/valet services; I'm quite sure you'll find the
Amenities & Services at Disney's Old Key West Resort to be excellent.
If I can help sprinkle any extra pixie dust onto your upcoming July holiday to Walt Disney World Resort please pop back to ask me another question.
Have a great Disney day.
~ Jane