The bus system introduced a new method of payment last year - it is a chip card that when read by an e-reader in each bus will automatically debit either the daily fare or the monthly pass. I think I will keep one of these cards loaded and ready for interim use (one more in the BOB) if I ever need to use alternate transporation again. It's convenient and never expires and more likely to be used in case I can never find any change in my pocket! It carries no personal information only the fares and the route numbers.
My local bus has a similar card. It expires after 2 years, though. I have one for convenience (and a 25% discount), but it's not essential in emergencies because the bus driver will give change.
The main thing I've done is find somewhere to live close (but not too close) to where I work. Nowadays I normally drive, but once a week I take the bus in and walk home.