I have a few buckets for large expenses. My budget includes 1.5% of house value per year ($2,700), I have a separate "one time expenses" budget of $3k annually (this will cover replacing cars and anything that the $2700 in house repairs dont cover). I also have $100k held outside my portfolio to "prime the kitty" for these types of things.
Original ER date set at Aug, 2013 (age 50). Succumbed to
OTMY syndrome. New target of March 2015 (age 52).
No sense retiring if you can't sleep at night worrying if you have enough "cushion" in your numbers.