What to do with my honda civic? Sell it or repair and keep it?

I have a 2000 Honda civic with 180 000m on it and it hasbeen in the garage essentially since January (6 months). I usually use my parents second car. The car will not be really used by me for another year. As it as been in the garage for a while it needs an oxygen sensor replacement, and seems like the batter is dead ( car won't start without jumper cables). I assume the brakes are rusty as well. How much do you think it will cost to get this back in running shape?
Is it better to just keep the car until I need it in a year or use it in a trade in. Or do i try to sell it as is and take much less money for it.

Added (1). *180 000km

It will cost at least $500 or more to fix
Fix it sell for What you can with that many miles you going to keep having problems get rid of it!

Why don't you take ti to a shop that will quote you on what it needs so you actually know for sure what is needed. Right now it is just a guessing game.

you don't necessarily need a o2 sensor unless something happened to make it go bad or it was bad before. Normally running some cleaner and new fuel for a while will clean off the old crud off the sensor and your good to go.