have you looked at the Tamiya thinner in the 250ml container?
i got my LHS to stock it. it is $7 or $7.50 for 250ml,
instead of $3 for 50ml.
and YES, i know that is still more expensive than tap water, rubbing alcohol, windshield washer fluid,
gasoline, milk, beer, and a great number of other things.
but it is not prohibitively expensive, and there is no concern of failure.
and 250ml goes a long way.
think of it as a half price sale on Tamiya thinner.
ed.