Ive been living on my own now for 2 years and its amazing. I never had to deal with costs of utilities or rent before so it was all new to me back then but I learned pretty quickly.
$300 utilities does seem a little high - even with the absurd cost of shipping gas/electricity/water in addition to internet and phones I cant see a single person paying more than $200 unless you get some primo package. This is assuming you don't get TV because by the sounds of it your schedule isn't going to really permit that kind of free time.
Best tip is to get a roommate. The problem with utilities is not the basic cost but the shipping - for my bills (in a house of 4) it accounts for about $100 of a $250 monthly bill. By splitting this fixed cost you are able to reduce your costs dramatically.
As for getting a job ever university is a bit different. Mine is really pro-active for helping struggling students find some placement in the University. Mostly the jobs are mundane such as working at one of the Cafeteria's, but sometimes you get cool ones like being an assistant for electro fishing (my roommates summer job).
Trying to get 40hrs a week and school is really going to be pushing it. Heck right now I only have about 12 hours of lectures a week but the readings is what absolutely kills me. I spend at least 20-30 hours a week reading the books and taking notes in addition to homework and assignments - add another 10 hours to that during midterms. See if your university will offer some kind of financial aid (lots around here have great programs) because you won't make tuition in addition to costs of living.
And finally some money saving tips:
-if you have to buy food at the school try to find the grad student caf/lounge they tend to price everything AT cost. At my school they sell the same things as the other resturants but a 30 second elevator ride saves me $1.20 on a plate of quesadeas
-If you can buy in bulk (costco is amazing for this)
-Carry larger bills rather than smaller ones as you are less likely to spend on useless things when you have to break a $50
-Networking with people is a great way of finding new and better jobs, a few of my friends had to give up their current job to do field research and they made sure their friends got those positions before anyone could post a job opening
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