Wow, assuming that's in good shape that is a great deal. I sold a single speed Townie for $165 barely trying.

Since you were looking at SB C/L, I assume you might be attending UCSB or nearby. My niece went there, lost a bike a year so buy a good U lock, and always lock it.

3 main things for maintenance:

1) the steel parts will rust being near the ocean, keep the chain lubed.
2) Nothing kills tires more than under inflation. Keep them pumped up. Check every week or two.
3) Depending on how much you ride it, if the gears don't shift correctly, the deraileur (or mount) may be bent or the cable may be stretched. Keep it tuned up and look on Youtube for tips. At first deraileurs are intimidating but they are pretty simple once you get the hang of things. I would have gone with a single speed for simplicity but that's a great bike.

Bonus:4) keep the brakes tuned up for when you REALLY need them. 5) Oh and grab a light. Awesome rechargeable lights from Performance are cheap now (<$50) and make a huge difference in night riding. Anything 300 lumens or more from a name brand will be more than sufficient. They clip onto the handlebar and when you park it, you just slide it off, pocket it and off you go.

Have fun.