And steal the duvet
Because it had two tennis courts and my girlfriend liked giving tennis parties, I rented a bigger house than a bachelor needed while the owner was Ambassador in London. His son, an acquaintance rather than a chum, sold his house and I offered him a bunk until he found somewhere. Then my socks started disappearing. Into his sock drawer. Well, of course the servants were his family's servants, not mine. "Oh no, these Mr Heinrich's socks. We know his socks." So in my house, many years later, when my socks are swallowed by the washing machine, we says, "Heinrich is alive and well and living in our washing machine!"
To bring the thread back on topic, you should of course carry a good quality banknote in your toolkit as well, to use as a tyre patch (sock) if necessary. A toolkit could also be a good place to put a tightly rolled emergency banknote, perhaps in a tiny vial, with some small tools to dirty it up a little so it isn't immediately obvious as money.
I'd be hesitant about carrying anything as an emergency fund above a unit of fifty in most currencies. I've several had shopkeepers who've known me for years refuse to take a €100 bill on principle, because it is a favorite of the forgers.
Andre Jute