This is awful. Sorry to hear about the unnecessary expense.
I don't mean to sidejack your post, but it got me thinking about one of my taps that needs a new washer soon. Obviously I would need to figure out what size washer to buy for them (I may as well change all the washers when I replace the leaky one), but how would one tell the difference?
I don't want to buy the wrong ones, turn off the water supply, open the tap up, see that it's the incorrect size, have to button the tap up again and wait for the geyser to refill (doubt the geyser has a shut-off valve installed on the outlet), go and buy more washers and repeat the process.
Or should I just buy multiple sizes and hope for the best?