Hello mate,
I'am a frenchie who returned in australia 4 months ago now. Living in st kilda close to the beach is possible, but you should consider raising your rent, for 200 dollars is really cheap. I guess you could found something cheap, but you need to be aware that sometime cheap places are also a little bit dirty. There's plenty of street close to the beach where you could get accommodation.It will be better for you to arrive before summer season kicks in 'cause people are going to raise their rent at an unbelievable level.
As i am working in a café, i'm telling you : don't do that. They will hire you only for busy days, your rate will be less than 15 bucks an hour. During summer you'll be very busy and they will get rid of you when season ends. This is not a general rule, but something many people have experienced. You might try, and luckily end up in a good position where this is not exploitation. I'm returning to my first occupation for I don't make enough money, just barely enough to live. For whv, most of the time you can land jobs others people doesn't want : fruitpicking and other **** jobs.
My advice would be to keep trying landing a job in relation with your resume.
Most café will require any experience, but if you still want it, you can do a course to learn difference between their many coffees.
As for kiting, there is plenty of spots around st kilda just check this website :
www.greenlivingpedia.org/Victorian_kitesurfing_locations