The battery in my car is fucked and needs to be replaced. How easy is it to change it yourself? I haven't done much stuff on cars but I'm not afraid of DIY stuff.
The battery looks like it is very accessible and that all it takes is to unscrew a few bolts.
Some auto parts stores will install it for free, and usually give you some money back for your old battery (core deposit or something). Just make sure it's the right size and has enough amps - for instance if your car is a diesel it needs more.
Big box store batteries are cheaper, but generally not as good. But it doesn't matter much, all car batteries work fine.
Don't toss the old battery in the ocean, please.