We did the bus to SW from POP and a cab back to POP. We spent $2 each ont he way there...not a bad bus ride, it does drop you off at the END of the SW parking lot, but for $6 it was just fine...Then at the end of the day when we were all pooped, I spent about $25 back to POP.
Our other option was to rent a car, I fgured I spent $36 for the day (including tip) and didn't pay for parking,....so it was worth it for me.